diff --git a/assets/api/writer-generator/python/profile_helpers.py b/assets/api/writer-generator/python/profile_helpers.py
index 0cc130a2..f3146147 100644
--- a/assets/api/writer-generator/python/profile_helpers.py
+++ b/assets/api/writer-generator/python/profile_helpers.py
@@ -444,6 +444,29 @@ def validate_slice_cardinality(
     return errors
 
 
+def validate_slice_fields(
+    res: object,
+    profile_name: str,
+    field: str,
+    match: Mapping[str, Any],
+    slice_name: str,
+    required_fields: Sequence[str],
+) -> list[str]:
+    """Validates required fields within matched slice elements. For each array
+    item matching the discriminator, checks that the listed fields are present."""
+    items = _get_field(res, field) or []
+    if not isinstance(items, Iterable):
+        items = []
+    errors: list[str] = []
+    for item in items:
+        if not matches_value(item, match):
+            continue
+        for rf in required_fields:
+            if _get_field(item, rf) is None:
+                errors.append(f"{profile_name}.{field}[{slice_name}].{rf} is required")
+    return errors
+
+
 def validate_choice_required(res: object, profile_name: str, choices: Sequence[str]) -> list[str]:
     """Checks that at least one of the listed choice-type variants is present."""
     if any(_get_field(res, c) is not None for c in choices):
@@ -451,6 +474,17 @@ def validate_choice_required(res: object, profile_name: str, choices: Sequence[s
     return [f"{profile_name}: at least one of {', '.join(choices)} is required"]
 
 
+def validate_choice_prohibited(res: object, profile_name: str, prohibited: Sequence[str]) -> list[str]:
+    """Checks that none of the listed prohibited choice-type variants is present.
+    E.g. a profile narrowing ``value[x]`` to ``value_quantity`` prohibits every
+    other variant."""
+    return [
+        f"{profile_name}: field '{c}' must not be present"
+        for c in prohibited
+        if _get_field(res, c) is not None
+    ]
+
+
 def validate_enum(res: object, profile_name: str, field: str, allowed: Sequence[str]) -> list[str]:
     """Checks that the value of ``field`` has a code within ``allowed``.
     Handles plain strings, Coding, and CodeableConcept."""
diff --git a/examples/python-r4-us-core/fhir_types/example_folder_structures/profiles/bundle_example_typed_bundle.py b/examples/python-r4-us-core/fhir_types/example_folder_structures/profiles/bundle_example_typed_bundle.py
index 8455acf8..b22bb1e6 100644
--- a/examples/python-r4-us-core/fhir_types/example_folder_structures/profiles/bundle_example_typed_bundle.py
+++ b/examples/python-r4-us-core/fhir_types/example_folder_structures/profiles/bundle_example_typed_bundle.py
@@ -13,7 +13,7 @@
 from fhir_types.hl7_fhir_r4_core.resource import Resource
 from fhir_types.profile_helpers import (
     build_resource, ensure_profile, get_array_slice, get_array_slices, set_array_slice, set_array_slices, \
-    validate_slice_cardinality
+    validate_required, validate_slice_cardinality
 )
 
 
@@ -99,5 +99,6 @@ def validate(self) -> dict[str, list[str]]:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "entry", {"resource":{"resourceType":"Patient"}}, "PatientEntry", 1, 1))
+        errors.extend(validate_required(self._resource, profile_name, "type"))
         return {"errors": errors, "warnings": warnings}
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/base.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/base.py
index a8d255ca..a3b5662a 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/base.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/base.py
@@ -61,7 +61,7 @@ class Age(Quantity):
 
 class Annotation(Element):
     model_config = ConfigDict(validate_by_name=True, serialize_by_alias=True, extra="forbid")
-    authorReference: Reference | None = Field(None, alias="authorReference", serialization_alias="authorReference")
+    authorReference: Reference[Literal["Organization", "Patient", "Practitioner", "RelatedPerson"]] | None = Field(None, alias="authorReference", serialization_alias="authorReference")
     authorString: str | None = Field(None, alias="authorString", serialization_alias="authorString")
     authorStringExtension: Element | None = Field(None, alias="_authorString", serialization_alias="_authorString")
     text: str = Field(alias="text", serialization_alias="text")
@@ -183,7 +183,7 @@ class DataRequirement(Element):
     profileExtension: PyList[Element | None] | None = Field(None, alias="_profile", serialization_alias="_profile")
     sort: PyList[DataRequirementSort] | None = Field(None, alias="sort", serialization_alias="sort")
     subjectCodeableConcept: CodeableConcept | None = Field(None, alias="subjectCodeableConcept", serialization_alias="subjectCodeableConcept")
-    subjectReference: Reference | None = Field(None, alias="subjectReference", serialization_alias="subjectReference")
+    subjectReference: Reference[Literal["Group"]] | None = Field(None, alias="subjectReference", serialization_alias="subjectReference")
     type: str = Field(alias="type", serialization_alias="type")
     typeExtension: Element | None = Field(None, alias="_type", serialization_alias="_type")
 
@@ -346,7 +346,7 @@ class HumanName(Element):
 
 class Identifier(Element):
     model_config = ConfigDict(validate_by_name=True, serialize_by_alias=True, extra="forbid")
-    assigner: Reference | None = Field(None, alias="assigner", serialization_alias="assigner")
+    assigner: Reference[Literal["Organization"]] | None = Field(None, alias="assigner", serialization_alias="assigner")
     period: Period | None = Field(None, alias="period", serialization_alias="period")
     system: str | None = Field(None, alias="system", serialization_alias="system")
     systemExtension: Element | None = Field(None, alias="_system", serialization_alias="_system")
@@ -425,14 +425,14 @@ class Ratio(Element):
     numerator: Quantity | None = Field(None, alias="numerator", serialization_alias="numerator")
 
 
-class Reference(Element):
+class Reference(Element, Generic[T]):
     model_config = ConfigDict(validate_by_name=True, serialize_by_alias=True, extra="forbid")
     display: str | None = Field(None, alias="display", serialization_alias="display")
     displayExtension: Element | None = Field(None, alias="_display", serialization_alias="_display")
     identifier: Identifier | None = Field(None, alias="identifier", serialization_alias="identifier")
     reference: str | None = Field(None, alias="reference", serialization_alias="reference")
     referenceExtension: Element | None = Field(None, alias="_reference", serialization_alias="_reference")
-    type: str | None = Field(None, alias="type", serialization_alias="type")
+    type: T | None = Field(None, alias="type", serialization_alias="type")
     typeExtension: Element | None = Field(None, alias="_type", serialization_alias="_type")
 
 
@@ -474,7 +474,7 @@ class Signature(Element):
     model_config = ConfigDict(validate_by_name=True, serialize_by_alias=True, extra="forbid")
     data: str | None = Field(None, alias="data", serialization_alias="data")
     dataExtension: Element | None = Field(None, alias="_data", serialization_alias="_data")
-    onBehalfOf: Reference | None = Field(None, alias="onBehalfOf", serialization_alias="onBehalfOf")
+    onBehalfOf: Reference[Literal["Device", "Organization", "Patient", "Practitioner", "PractitionerRole", "RelatedPerson"]] | None = Field(None, alias="onBehalfOf", serialization_alias="onBehalfOf")
     sigFormat: str | None = Field(None, alias="sigFormat", serialization_alias="sigFormat")
     sigFormatExtension: Element | None = Field(None, alias="_sigFormat", serialization_alias="_sigFormat")
     targetFormat: str | None = Field(None, alias="targetFormat", serialization_alias="targetFormat")
@@ -482,7 +482,7 @@ class Signature(Element):
     type: PyList[Coding[Literal["1.2.840.10065.1.12.1.1", "1.2.840.10065.1.12.1.2", "1.2.840.10065.1.12.1.3", "1.2.840.10065.1.12.1.4", "1.2.840.10065.1.12.1.5", "1.2.840.10065.1.12.1.6", "1.2.840.10065.1.12.1.7", "1.2.840.10065.1.12.1.8", "1.2.840.10065.1.12.1.9", "1.2.840.10065.1.12.1.10", "1.2.840.10065.1.12.1.11", "1.2.840.10065.1.12.1.12", "1.2.840.10065.1.12.1.13", "1.2.840.10065.1.12.1.14", "1.2.840.10065.1.12.1.15", "1.2.840.10065.1.12.1.16", "1.2.840.10065.1.12.1.17", "1.2.840.10065.1.12.1.18"] | str]] = Field(alias="type", serialization_alias="type")
     when: str = Field(alias="when", serialization_alias="when")
     whenExtension: Element | None = Field(None, alias="_when", serialization_alias="_when")
-    who: Reference = Field(alias="who", serialization_alias="who")
+    who: Reference[Literal["Device", "Organization", "Patient", "Practitioner", "PractitionerRole", "RelatedPerson"]] = Field(alias="who", serialization_alias="who")
 
 
 class TimingRepeat(Element):
@@ -524,7 +524,7 @@ class TriggerDefinition(Element):
     timingDateExtension: Element | None = Field(None, alias="_timingDate", serialization_alias="_timingDate")
     timingDateTime: str | None = Field(None, alias="timingDateTime", serialization_alias="timingDateTime")
     timingDateTimeExtension: Element | None = Field(None, alias="_timingDateTime", serialization_alias="_timingDateTime")
-    timingReference: Reference | None = Field(None, alias="timingReference", serialization_alias="timingReference")
+    timingReference: Reference[Literal["Schedule"]] | None = Field(None, alias="timingReference", serialization_alias="timingReference")
     timingTiming: Timing | None = Field(None, alias="timingTiming", serialization_alias="timingTiming")
     type: Literal["named-event", "periodic", "data-changed", "data-added", "data-modified", "data-removed", "data-accessed", "data-access-ended"] = Field(alias="type", serialization_alias="type")
     typeExtension: Element | None = Field(None, alias="_type", serialization_alias="_type")
@@ -536,6 +536,6 @@ class UsageContext(Element):
     valueCodeableConcept: CodeableConcept | None = Field(None, alias="valueCodeableConcept", serialization_alias="valueCodeableConcept")
     valueQuantity: Quantity | None = Field(None, alias="valueQuantity", serialization_alias="valueQuantity")
     valueRange: Range | None = Field(None, alias="valueRange", serialization_alias="valueRange")
-    valueReference: Reference | None = Field(None, alias="valueReference", serialization_alias="valueReference")
+    valueReference: Reference[Literal["Group", "HealthcareService", "InsurancePlan", "Location", "Organization", "PlanDefinition", "ResearchStudy"]] | None = Field(None, alias="valueReference", serialization_alias="valueReference")
 
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/observation.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/observation.py
index 2807d46f..f108ee6f 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/observation.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/observation.py
@@ -52,36 +52,36 @@ class Observation(DomainResource):
         serialization_alias='resourceType',
         pattern='Observation'
     )
-    basedOn: PyList[Reference] | None = Field(None, alias="basedOn", serialization_alias="basedOn")
+    basedOn: PyList[Reference[Literal["CarePlan", "DeviceRequest", "ImmunizationRecommendation", "MedicationRequest", "NutritionOrder", "ServiceRequest"]]] | None = Field(None, alias="basedOn", serialization_alias="basedOn")
     bodySite: CodeableConcept | None = Field(None, alias="bodySite", serialization_alias="bodySite")
     category: PyList[CodeableConcept[Literal["social-history", "vital-signs", "imaging", "laboratory", "procedure", "survey", "exam", "therapy", "activity"] | str]] | None = Field(None, alias="category", serialization_alias="category")
     code: CodeableConcept = Field(alias="code", serialization_alias="code")
     component: PyList[ObservationComponent] | None = Field(None, alias="component", serialization_alias="component")
     dataAbsentReason: CodeableConcept[Literal["unknown", "asked-unknown", "temp-unknown", "not-asked", "asked-declined", "masked", "not-applicable", "unsupported", "as-text", "error", "not-a-number", "negative-infinity", "positive-infinity", "not-performed", "not-permitted"] | str] | None = Field(None, alias="dataAbsentReason", serialization_alias="dataAbsentReason")
-    derivedFrom: PyList[Reference] | None = Field(None, alias="derivedFrom", serialization_alias="derivedFrom")
-    device: Reference | None = Field(None, alias="device", serialization_alias="device")
+    derivedFrom: PyList[Reference[Literal["DocumentReference", "ImagingStudy", "Media", "MolecularSequence", "Observation", "QuestionnaireResponse"]]] | None = Field(None, alias="derivedFrom", serialization_alias="derivedFrom")
+    device: Reference[Literal["Device", "DeviceMetric"]] | None = Field(None, alias="device", serialization_alias="device")
     effectiveDateTime: str | None = Field(None, alias="effectiveDateTime", serialization_alias="effectiveDateTime")
     effectiveDateTimeExtension: Element | None = Field(None, alias="_effectiveDateTime", serialization_alias="_effectiveDateTime")
     effectiveInstant: str | None = Field(None, alias="effectiveInstant", serialization_alias="effectiveInstant")
     effectiveInstantExtension: Element | None = Field(None, alias="_effectiveInstant", serialization_alias="_effectiveInstant")
     effectivePeriod: Period | None = Field(None, alias="effectivePeriod", serialization_alias="effectivePeriod")
     effectiveTiming: Timing | None = Field(None, alias="effectiveTiming", serialization_alias="effectiveTiming")
-    encounter: Reference | None = Field(None, alias="encounter", serialization_alias="encounter")
+    encounter: Reference[Literal["Encounter"]] | None = Field(None, alias="encounter", serialization_alias="encounter")
     focus: PyList[Reference] | None = Field(None, alias="focus", serialization_alias="focus")
-    hasMember: PyList[Reference] | None = Field(None, alias="hasMember", serialization_alias="hasMember")
+    hasMember: PyList[Reference[Literal["MolecularSequence", "Observation", "QuestionnaireResponse"]]] | None = Field(None, alias="hasMember", serialization_alias="hasMember")
     identifier: PyList[Identifier] | None = Field(None, alias="identifier", serialization_alias="identifier")
     interpretation: PyList[CodeableConcept[Literal["_GeneticObservationInterpretation", "CAR", "Carrier", "_ObservationInterpretationChange", "B", "D", "U", "W", "_ObservationInterpretationExceptions", "<", ">", "AC", "IE", "QCF", "TOX", "_ObservationInterpretationNormality", "A", "AA", "HH", "LL", "H", "H>", "HU", "L", "L<", "LU", "N", "_ObservationInterpretationSusceptibility", "I", "MS", "NCL", "NS", "R", "SYN-R", "S", "SDD", "SYN-S", "VS", "EX", "HX", "LX", "HM", "ObservationInterpretationDetection", "IND", "E", "NEG", "ND", "POS", "DET", "ObservationInterpretationExpectation", "EXP", "UNE", "OBX", "ReactivityObservationInterpretation", "NR", "RR", "WR"] | str]] | None = Field(None, alias="interpretation", serialization_alias="interpretation")
     issued: str | None = Field(None, alias="issued", serialization_alias="issued")
     issuedExtension: Element | None = Field(None, alias="_issued", serialization_alias="_issued")
     method: CodeableConcept | None = Field(None, alias="method", serialization_alias="method")
     note: PyList[Annotation] | None = Field(None, alias="note", serialization_alias="note")
-    partOf: PyList[Reference] | None = Field(None, alias="partOf", serialization_alias="partOf")
-    performer: PyList[Reference] | None = Field(None, alias="performer", serialization_alias="performer")
+    partOf: PyList[Reference[Literal["ImagingStudy", "Immunization", "MedicationAdministration", "MedicationDispense", "MedicationStatement", "Procedure"]]] | None = Field(None, alias="partOf", serialization_alias="partOf")
+    performer: PyList[Reference[Literal["CareTeam", "Organization", "Patient", "Practitioner", "PractitionerRole", "RelatedPerson"]]] | None = Field(None, alias="performer", serialization_alias="performer")
     referenceRange: PyList[ObservationReferenceRange] | None = Field(None, alias="referenceRange", serialization_alias="referenceRange")
-    specimen: Reference | None = Field(None, alias="specimen", serialization_alias="specimen")
+    specimen: Reference[Literal["Specimen"]] | None = Field(None, alias="specimen", serialization_alias="specimen")
     status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"] = Field(alias="status", serialization_alias="status")
     statusExtension: Element | None = Field(None, alias="_status", serialization_alias="_status")
-    subject: Reference | None = Field(None, alias="subject", serialization_alias="subject")
+    subject: Reference[Literal["Device", "Group", "Location", "Patient"]] | None = Field(None, alias="subject", serialization_alias="subject")
     valueBoolean: bool | None = Field(None, alias="valueBoolean", serialization_alias="valueBoolean")
     valueBooleanExtension: Element | None = Field(None, alias="_valueBoolean", serialization_alias="_valueBoolean")
     valueCodeableConcept: CodeableConcept | None = Field(None, alias="valueCodeableConcept", serialization_alias="valueCodeableConcept")
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/organization.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/organization.py
index cebea2a4..70c7b6f9 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/organization.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/organization.py
@@ -37,11 +37,11 @@ class Organization(DomainResource):
     alias: PyList[str] | None = Field(None, alias="alias", serialization_alias="alias")
     aliasExtension: PyList[Element | None] | None = Field(None, alias="_alias", serialization_alias="_alias")
     contact: PyList[OrganizationContact] | None = Field(None, alias="contact", serialization_alias="contact")
-    endpoint: PyList[Reference] | None = Field(None, alias="endpoint", serialization_alias="endpoint")
+    endpoint: PyList[Reference[Literal["Endpoint"]]] | None = Field(None, alias="endpoint", serialization_alias="endpoint")
     identifier: PyList[Identifier] | None = Field(None, alias="identifier", serialization_alias="identifier")
     name: str | None = Field(None, alias="name", serialization_alias="name")
     nameExtension: Element | None = Field(None, alias="_name", serialization_alias="_name")
-    partOf: Reference | None = Field(None, alias="partOf", serialization_alias="partOf")
+    partOf: Reference[Literal["Organization"]] | None = Field(None, alias="partOf", serialization_alias="partOf")
     telecom: PyList[ContactPoint] | None = Field(None, alias="telecom", serialization_alias="telecom")
     type: PyList[CodeableConcept] | None = Field(None, alias="type", serialization_alias="type")
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/patient.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/patient.py
index d9691092..5e1ae42d 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/patient.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/patient.py
@@ -25,14 +25,14 @@ class PatientContact(BackboneElement):
     address: Address | None = Field(None, alias="address", serialization_alias="address")
     gender: Literal["male", "female", "other", "unknown"] | None = Field(None, alias="gender", serialization_alias="gender")
     name: HumanName | None = Field(None, alias="name", serialization_alias="name")
-    organization: Reference | None = Field(None, alias="organization", serialization_alias="organization")
+    organization: Reference[Literal["Organization"]] | None = Field(None, alias="organization", serialization_alias="organization")
     period: Period | None = Field(None, alias="period", serialization_alias="period")
     relationship: PyList[CodeableConcept] | None = Field(None, alias="relationship", serialization_alias="relationship")
     telecom: PyList[ContactPoint] | None = Field(None, alias="telecom", serialization_alias="telecom")
 
 class PatientLink(BackboneElement):
     model_config = ConfigDict(validate_by_name=True, serialize_by_alias=True, extra="forbid")
-    other: Reference = Field(alias="other", serialization_alias="other")
+    other: Reference[Literal["Patient", "RelatedPerson"]] = Field(alias="other", serialization_alias="other")
     type: Literal["replaced-by", "replaces", "refer", "seealso"] = Field(alias="type", serialization_alias="type")
 
 
@@ -57,10 +57,10 @@ class Patient(DomainResource):
     deceasedDateTimeExtension: Element | None = Field(None, alias="_deceasedDateTime", serialization_alias="_deceasedDateTime")
     gender: Literal["male", "female", "other", "unknown"] | None = Field(None, alias="gender", serialization_alias="gender")
     genderExtension: Element | None = Field(None, alias="_gender", serialization_alias="_gender")
-    generalPractitioner: PyList[Reference] | None = Field(None, alias="generalPractitioner", serialization_alias="generalPractitioner")
+    generalPractitioner: PyList[Reference[Literal["Organization", "Practitioner", "PractitionerRole"]]] | None = Field(None, alias="generalPractitioner", serialization_alias="generalPractitioner")
     identifier: PyList[Identifier] | None = Field(None, alias="identifier", serialization_alias="identifier")
     link: PyList[PatientLink] | None = Field(None, alias="link", serialization_alias="link")
-    managingOrganization: Reference | None = Field(None, alias="managingOrganization", serialization_alias="managingOrganization")
+    managingOrganization: Reference[Literal["Organization"]] | None = Field(None, alias="managingOrganization", serialization_alias="managingOrganization")
     maritalStatus: CodeableConcept[Literal["A", "D", "I", "L", "M", "P", "S", "T", "U", "W", "UNK"] | str] | None = Field(None, alias="maritalStatus", serialization_alias="maritalStatus")
     multipleBirthBoolean: bool | None = Field(None, alias="multipleBirthBoolean", serialization_alias="multipleBirthBoolean")
     multipleBirthBooleanExtension: Element | None = Field(None, alias="_multipleBirthBoolean", serialization_alias="_multipleBirthBoolean")
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_birth_place.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_birth_place.py
index 5d7fd9e2..ca2d7e19 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_birth_place.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_birth_place.py
@@ -9,7 +9,7 @@
 from fhir_types.hl7_fhir_r4_core.base import Extension
 from fhir_types.hl7_fhir_r4_core.base import Address
 from fhir_types.profile_helpers import (
-    build_resource, validate_choice_required, validate_fixed_value, validate_required
+    build_resource, validate_choice_prohibited, validate_choice_required, validate_fixed_value, validate_required
 )
 
 
@@ -67,6 +67,13 @@ def validate(self) -> dict[str, list[str]]:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/StructureDefinition/patient-birthPlace"))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["valueAddress"]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "valueAddress"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueBase64binary","valueBoolean","valueCanonical","valueCode","valueDate","valueDateTime","valueDecimal","valueId","valueInstant","valueInteger","valueMarkdown","valueOid","valuePositiveInt","valueString","valueTime","valueUnsignedInt","valueUri","valueUrl","valueUuid","valueAge","valueAnnotation","valueAttachment","valueCodeableConcept","valueCoding","valueContactPoint","valueCount","valueDistance","valueDuration","valueHumanName","valueIdentifier","valueMoney","valuePeriod","valueQuantity","valueRange","valueRatio","valueReference","valueSampledData","valueSignature","valueTiming","valueContactDetail","valueContributor","valueDataRequirement","valueExpression","valueParameterDefinition","valueRelatedArtifact","valueTriggerDefinition","valueUsageContext","valueDosage","valueMeta"
+        ]))
         return {"errors": errors, "warnings": warnings}
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_birth_time.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_birth_time.py
index 6c6e0ee2..f3236787 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_birth_time.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_birth_time.py
@@ -8,7 +8,7 @@
 
 from fhir_types.hl7_fhir_r4_core.base import Extension
 from fhir_types.profile_helpers import (
-    build_resource, validate_choice_required, validate_fixed_value, validate_required
+    build_resource, validate_choice_prohibited, validate_choice_required, validate_fixed_value, validate_required
 )
 
 
@@ -66,6 +66,13 @@ def validate(self) -> dict[str, list[str]]:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/StructureDefinition/patient-birthTime"))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["valueDateTime"]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "valueDateTime"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueBase64binary","valueBoolean","valueCanonical","valueCode","valueDate","valueDecimal","valueId","valueInstant","valueInteger","valueMarkdown","valueOid","valuePositiveInt","valueString","valueTime","valueUnsignedInt","valueUri","valueUrl","valueUuid","valueAddress","valueAge","valueAnnotation","valueAttachment","valueCodeableConcept","valueCoding","valueContactPoint","valueCount","valueDistance","valueDuration","valueHumanName","valueIdentifier","valueMoney","valuePeriod","valueQuantity","valueRange","valueRatio","valueReference","valueSampledData","valueSignature","valueTiming","valueContactDetail","valueContributor","valueDataRequirement","valueExpression","valueParameterDefinition","valueRelatedArtifact","valueTriggerDefinition","valueUsageContext","valueDosage","valueMeta"
+        ]))
         return {"errors": errors, "warnings": warnings}
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_own_prefix.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_own_prefix.py
index 1daa8953..a99f8b95 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_own_prefix.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/extension_own_prefix.py
@@ -8,7 +8,7 @@
 
 from fhir_types.hl7_fhir_r4_core.base import Extension
 from fhir_types.profile_helpers import (
-    build_resource, validate_choice_required, validate_fixed_value, validate_required
+    build_resource, validate_choice_prohibited, validate_choice_required, validate_fixed_value, validate_required
 )
 
 
@@ -66,6 +66,13 @@ def validate(self) -> dict[str, list[str]]:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/StructureDefinition/humanname-own-prefix"))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["valueString"]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "valueString"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueBase64binary","valueBoolean","valueCanonical","valueCode","valueDate","valueDateTime","valueDecimal","valueId","valueInstant","valueInteger","valueMarkdown","valueOid","valuePositiveInt","valueTime","valueUnsignedInt","valueUri","valueUrl","valueUuid","valueAddress","valueAge","valueAnnotation","valueAttachment","valueCodeableConcept","valueCoding","valueContactPoint","valueCount","valueDistance","valueDuration","valueHumanName","valueIdentifier","valueMoney","valuePeriod","valueQuantity","valueRange","valueRatio","valueReference","valueSampledData","valueSignature","valueTiming","valueContactDetail","valueContributor","valueDataRequirement","valueExpression","valueParameterDefinition","valueRelatedArtifact","valueTriggerDefinition","valueUsageContext","valueDosage","valueMeta"
+        ]))
         return {"errors": errors, "warnings": warnings}
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/observation_observation_bodyweight.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/observation_observation_bodyweight.py
index 05054783..5a8b04d0 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/observation_observation_bodyweight.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/observation_observation_bodyweight.py
@@ -10,8 +10,8 @@
 from fhir_types.hl7_fhir_r4_core.base import CodeableConcept, Period, Quantity, Reference
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \
-    set_array_slice, strip_match_keys, validate_choice_required, validate_enum, validate_fixed_value, validate_must_support, \
-    validate_reference, validate_required, validate_slice_cardinality
+    set_array_slice, strip_match_keys, validate_choice_prohibited, validate_choice_required, validate_enum, \
+    validate_fixed_value, validate_must_support, validate_reference, validate_required, validate_slice_cardinality
 )
 
 
@@ -46,7 +46,7 @@ def apply(cls, resource: Observation) -> "ObservationBodyweightProfile":
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
 
         return build_resource(
@@ -60,7 +60,7 @@ def create_resource(cls, *, category: list[CodeableConcept] | None = None, statu
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> "ObservationBodyweightProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> "ObservationBodyweightProfile":
         return cls.apply(cls.create_resource(category=category, status=status, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -73,10 +73,10 @@ def set_status(self, value: Literal["registered", "preliminary", "final", "amend
         setattr(self._resource, "status", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "ObservationBodyweightProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "ObservationBodyweightProfile":
         setattr(self._resource, "subject", value)
         return self
 
@@ -143,19 +143,51 @@ def validate(self) -> dict[str, list[str]]:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "code", {"coding":[{"code":"29463-7","system":"http://loinc.org"}]}))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["85353-1","9279-1","8867-4","2708-6","8310-5","8302-2","9843-4","29463-7","39156-5","85354-9","8480-6","8462-4","8478-0"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueCodeableConcept","valueString","valueBoolean","valueInteger","valueRange","valueRatio","valueSampledData","valueTime","valueDateTime","valuePeriod"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "85353-1","9279-1","8867-4","2708-6","8310-5","8302-2","9843-4","29463-7","39156-5","85354-9","8480-6","8462-4","8478-0"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         return {"errors": errors, "warnings": warnings}
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/observation_observation_vitalsigns.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/observation_observation_vitalsigns.py
index b9c29cd0..12dbd1b6 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/observation_observation_vitalsigns.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_r4_core/profiles/observation_observation_vitalsigns.py
@@ -10,8 +10,8 @@
 from fhir_types.hl7_fhir_r4_core.base import CodeableConcept, Period, Reference
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \
-    set_array_slice, strip_match_keys, validate_choice_required, validate_enum, validate_must_support, validate_reference, \
-    validate_required, validate_slice_cardinality
+    set_array_slice, strip_match_keys, validate_choice_prohibited, validate_choice_required, validate_enum, \
+    validate_must_support, validate_reference, validate_required, validate_slice_cardinality
 )
 
 
@@ -46,7 +46,7 @@ def apply(cls, resource: Observation) -> "ObservationVitalsignsProfile":
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], code: CodeableConcept, subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], code: CodeableConcept, subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
 
         return build_resource(
@@ -60,7 +60,7 @@ def create_resource(cls, *, category: list[CodeableConcept] | None = None, statu
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], code: CodeableConcept, subject: Reference) -> "ObservationVitalsignsProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], code: CodeableConcept, subject: Reference[Literal["Patient"]]) -> "ObservationVitalsignsProfile":
         return cls.apply(cls.create_resource(category=category, status=status, code=code, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -80,10 +80,10 @@ def set_code(self, value: CodeableConcept) -> "ObservationVitalsignsProfile":
         setattr(self._resource, "code", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "ObservationVitalsignsProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "ObservationVitalsignsProfile":
         setattr(self._resource, "subject", value)
         return self
 
@@ -136,18 +136,46 @@ def validate(self) -> dict[str, list[str]]:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["85353-1","9279-1","8867-4","2708-6","8310-5","8302-2","9843-4","29463-7","39156-5","85354-9","8480-6","8462-4","8478-0"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "85353-1","9279-1","8867-4","2708-6","8310-5","8302-2","9843-4","29463-7","39156-5","85354-9","8480-6","8462-4","8478-0"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         return {"errors": errors, "warnings": warnings}
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_ethnicity_extension.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_ethnicity_extension.py
index 45993ecb..df04873c 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_ethnicity_extension.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_ethnicity_extension.py
@@ -11,7 +11,7 @@
 from fhir_types.profile_helpers import (
     _get_key, apply_slice_match, build_resource, ensure_slice_defaults, get_array_slice, get_extension_value, \
     is_extension, is_record, matches_value, push_extension, set_array_slice, strip_match_keys, unwrap_slice_choice, \
-    validate_fixed_value, validate_required, validate_slice_cardinality, wrap_slice_choice
+    validate_fixed_value, validate_required, validate_slice_cardinality, validate_slice_fields, wrap_slice_choice
 )
 
 
@@ -215,7 +215,19 @@ def validate(self) -> dict[str, list[str]]:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "extension"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "extension", {"url":"ombCategory"}, "ombCategory", 0, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"ombCategory"}, "ombCategory", [
+                "value","valueCoding"
+        ]))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"detailed"}, "detailed", [
+                "value","valueCoding"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "extension", {"url":"text"}, "text", 1, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"text"}, "text", [
+                "value","valueString"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/us/core/StructureDefinition/us-core-ethnicity"))
         return {"errors": errors, "warnings": warnings}
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_individual_sex_extension.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_individual_sex_extension.py
index b011b1df..60431896 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_individual_sex_extension.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_individual_sex_extension.py
@@ -9,7 +9,7 @@
 from fhir_types.hl7_fhir_r4_core.base import Extension
 from fhir_types.hl7_fhir_r4_core.base import Coding
 from fhir_types.profile_helpers import (
-    build_resource, validate_choice_required, validate_fixed_value, validate_required
+    build_resource, validate_choice_prohibited, validate_choice_required, validate_fixed_value, validate_required
 )
 
 
@@ -67,6 +67,13 @@ def validate(self) -> dict[str, list[str]]:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/us/core/StructureDefinition/us-core-individual-sex"))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["valueCoding"]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "valueCoding"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueBase64binary","valueBoolean","valueCanonical","valueCode","valueDate","valueDateTime","valueDecimal","valueId","valueInstant","valueInteger","valueMarkdown","valueOid","valuePositiveInt","valueString","valueTime","valueUnsignedInt","valueUri","valueUrl","valueUuid","valueAddress","valueAge","valueAnnotation","valueAttachment","valueCodeableConcept","valueContactPoint","valueCount","valueDistance","valueDuration","valueHumanName","valueIdentifier","valueMoney","valuePeriod","valueQuantity","valueRange","valueRatio","valueReference","valueSampledData","valueSignature","valueTiming","valueContactDetail","valueContributor","valueDataRequirement","valueExpression","valueParameterDefinition","valueRelatedArtifact","valueTriggerDefinition","valueUsageContext","valueDosage","valueMeta"
+        ]))
         return {"errors": errors, "warnings": warnings}
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_interpreter_needed_extension.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_interpreter_needed_extension.py
index 9d9fdb47..a6237749 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_interpreter_needed_extension.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_interpreter_needed_extension.py
@@ -9,7 +9,7 @@
 from fhir_types.hl7_fhir_r4_core.base import Extension
 from fhir_types.hl7_fhir_r4_core.base import Coding
 from fhir_types.profile_helpers import (
-    build_resource, validate_choice_required, validate_fixed_value, validate_required
+    build_resource, validate_choice_prohibited, validate_choice_required, validate_fixed_value, validate_required
 )
 
 
@@ -67,6 +67,13 @@ def validate(self) -> dict[str, list[str]]:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/us/core/StructureDefinition/us-core-interpreter-needed"))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["valueCoding"]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "valueCoding"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueBase64binary","valueBoolean","valueCanonical","valueCode","valueDate","valueDateTime","valueDecimal","valueId","valueInstant","valueInteger","valueMarkdown","valueOid","valuePositiveInt","valueString","valueTime","valueUnsignedInt","valueUri","valueUrl","valueUuid","valueAddress","valueAge","valueAnnotation","valueAttachment","valueCodeableConcept","valueContactPoint","valueCount","valueDistance","valueDuration","valueHumanName","valueIdentifier","valueMoney","valuePeriod","valueQuantity","valueRange","valueRatio","valueReference","valueSampledData","valueSignature","valueTiming","valueContactDetail","valueContributor","valueDataRequirement","valueExpression","valueParameterDefinition","valueRelatedArtifact","valueTriggerDefinition","valueUsageContext","valueDosage","valueMeta"
+        ]))
         return {"errors": errors, "warnings": warnings}
 
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_race_extension.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_race_extension.py
index 06ee4abe..34bb4b32 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_race_extension.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_race_extension.py
@@ -11,7 +11,7 @@
 from fhir_types.profile_helpers import (
     _get_key, apply_slice_match, build_resource, ensure_slice_defaults, get_array_slice, get_extension_value, \
     is_extension, is_record, matches_value, push_extension, set_array_slice, strip_match_keys, unwrap_slice_choice, \
-    validate_fixed_value, validate_required, validate_slice_cardinality, wrap_slice_choice
+    validate_fixed_value, validate_required, validate_slice_cardinality, validate_slice_fields, wrap_slice_choice
 )
 
 
@@ -218,7 +218,19 @@ def validate(self) -> dict[str, list[str]]:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "extension"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "extension", {"url":"ombCategory"}, "ombCategory", 0, 6))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"ombCategory"}, "ombCategory", [
+                "value","valueCoding"
+        ]))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"detailed"}, "detailed", [
+                "value","valueCoding"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "extension", {"url":"text"}, "text", 1, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"text"}, "text", [
+                "value","valueString"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/us/core/StructureDefinition/us-core-race"))
         return {"errors": errors, "warnings": warnings}
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_tribal_affiliation_extension.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_tribal_affiliation_extension.py
index fc418b50..de5dc3c9 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_tribal_affiliation_extension.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/extension_uscore_tribal_affiliation_extension.py
@@ -11,7 +11,7 @@
 from fhir_types.profile_helpers import (
     _get_key, apply_slice_match, build_resource, ensure_slice_defaults, get_array_slice, get_extension_value, \
     is_extension, is_record, matches_value, push_extension, set_array_slice, strip_match_keys, unwrap_slice_choice, \
-    validate_fixed_value, validate_required, validate_slice_cardinality, wrap_slice_choice
+    validate_fixed_value, validate_required, validate_slice_cardinality, validate_slice_fields, wrap_slice_choice
 )
 
 
@@ -165,7 +165,15 @@ def validate(self) -> dict[str, list[str]]:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "extension"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "extension", {"url":"tribalAffiliation"}, "tribalAffiliation", 1, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"tribalAffiliation"}, "tribalAffiliation", [
+                "value","valueCodeableConcept"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "extension", {"url":"isEnrolled"}, "isEnrolled", 0, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"isEnrolled"}, "isEnrolled", [
+                "value","valueBoolean"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/us/core/StructureDefinition/us-core-tribal-affiliation"))
         return {"errors": errors, "warnings": warnings}
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_blood_pressure_profile.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_blood_pressure_profile.py
index 6ee1c5ea..36bb4253 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_blood_pressure_profile.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_blood_pressure_profile.py
@@ -13,8 +13,9 @@
 from fhir_types.hl7_fhir_r4_core.observation import ObservationComponent
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \
-    set_array_slice, strip_match_keys, unwrap_slice_choice, validate_choice_required, validate_enum, validate_fixed_value, \
-    validate_must_support, validate_reference, validate_required, validate_slice_cardinality, wrap_slice_choice
+    set_array_slice, strip_match_keys, unwrap_slice_choice, validate_choice_prohibited, validate_choice_required, \
+    validate_enum, validate_fixed_value, validate_must_support, validate_reference, validate_required, validate_slice_cardinality, \
+    validate_slice_fields, wrap_slice_choice
 )
 
 
@@ -51,7 +52,7 @@ def apply(cls, resource: Observation) -> "UscoreBloodPressureProfile":
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
         component_with_defaults = ensure_slice_defaults(
             list(component or []),
@@ -71,7 +72,7 @@ def create_resource(cls, *, category: list[CodeableConcept] | None = None, compo
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> "UscoreBloodPressureProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> "UscoreBloodPressureProfile":
         return cls.apply(cls.create_resource(category=category, component=component, status=status, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -84,10 +85,10 @@ def set_status(self, value: Literal["registered", "preliminary", "final", "amend
         setattr(self._resource, "status", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "UscoreBloodPressureProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "UscoreBloodPressureProfile":  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
         setattr(self._resource, "subject", value)
         return self
 
@@ -385,22 +386,61 @@ def validate(self) -> dict[str, list[str]]:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "code", {"coding":[{"system":"http://loinc.org","code":"85354-9"}]}))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8480-6"}]}}, "systolic", 1, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8480-6"}]}}, "systolic", [
+                "valueQuantity"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", 1, 1))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", [
+                "valueQuantity"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "performer", [
+                "PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         warnings.extend(validate_must_support(self._resource, profile_name, "performer"))
         return {"errors": errors, "warnings": warnings}
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_body_weight_profile.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_body_weight_profile.py
index 00254658..eaf48475 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_body_weight_profile.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_body_weight_profile.py
@@ -12,8 +12,8 @@
 )
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \
-    set_array_slice, strip_match_keys, validate_choice_required, validate_enum, validate_excluded, validate_fixed_value, \
-    validate_must_support, validate_reference, validate_required, validate_slice_cardinality
+    set_array_slice, strip_match_keys, validate_choice_prohibited, validate_choice_required, validate_enum, \
+    validate_fixed_value, validate_must_support, validate_reference, validate_required, validate_slice_cardinality
 )
 
 
@@ -48,7 +48,7 @@ def apply(cls, resource: Observation) -> "UscoreBodyWeightProfile":
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
 
         return build_resource(
@@ -62,7 +62,7 @@ def create_resource(cls, *, category: list[CodeableConcept] | None = None, statu
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> "UscoreBodyWeightProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> "UscoreBodyWeightProfile":
         return cls.apply(cls.create_resource(category=category, status=status, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -75,10 +75,10 @@ def set_status(self, value: Literal["registered", "preliminary", "final", "amend
         setattr(self._resource, "status", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "UscoreBodyWeightProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "UscoreBodyWeightProfile":  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
         setattr(self._resource, "subject", value)
         return self
 
@@ -215,30 +215,55 @@ def validate(self) -> dict[str, list[str]]:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "code", {"coding":[{"system":"http://loinc.org","code":"29463-7"}]}))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueCodeableConcept"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueString"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueBoolean"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueInteger"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueRange"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueRatio"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueSampledData"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueTime"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueDateTime"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valuePeriod"))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "performer", [
+                "PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueCodeableConcept","valueString","valueBoolean","valueInteger","valueRange","valueRatio","valueSampledData","valueTime","valueDateTime","valuePeriod"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         warnings.extend(validate_must_support(self._resource, profile_name, "performer"))
         return {"errors": errors, "warnings": warnings}
diff --git a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_vital_signs_profile.py b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_vital_signs_profile.py
index bbbbb9e3..952d1347 100644
--- a/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_vital_signs_profile.py
+++ b/examples/python-r4-us-core/fhir_types/hl7_fhir_us_core/profiles/observation_uscore_vital_signs_profile.py
@@ -12,8 +12,8 @@
 )
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \
-    set_array_slice, strip_match_keys, validate_choice_required, validate_enum, validate_must_support, validate_reference, \
-    validate_required, validate_slice_cardinality
+    set_array_slice, strip_match_keys, validate_choice_prohibited, validate_choice_required, validate_enum, \
+    validate_must_support, validate_reference, validate_required, validate_slice_cardinality
 )
 
 
@@ -48,7 +48,7 @@ def apply(cls, resource: Observation) -> "UscoreVitalSignsProfile":
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], code: CodeableConcept, subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], code: CodeableConcept, subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
 
         return build_resource(
@@ -62,7 +62,7 @@ def create_resource(cls, *, category: list[CodeableConcept] | None = None, statu
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], code: CodeableConcept, subject: Reference) -> "UscoreVitalSignsProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], code: CodeableConcept, subject: Reference[Literal["Patient"]]) -> "UscoreVitalSignsProfile":
         return cls.apply(cls.create_resource(category=category, status=status, code=code, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -82,10 +82,10 @@ def set_code(self, value: CodeableConcept) -> "UscoreVitalSignsProfile":
         setattr(self._resource, "code", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "UscoreVitalSignsProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "UscoreVitalSignsProfile":  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
         setattr(self._resource, "subject", value)
         return self
 
@@ -325,19 +325,50 @@ def validate(self) -> dict[str, list[str]]:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "performer", [
+                "PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         warnings.extend(validate_must_support(self._resource, profile_name, "performer"))
         return {"errors": errors, "warnings": warnings}
diff --git a/examples/python-r4-us-core/fhir_types/profile_helpers.py b/examples/python-r4-us-core/fhir_types/profile_helpers.py
index 0cc130a2..f3146147 100644
--- a/examples/python-r4-us-core/fhir_types/profile_helpers.py
+++ b/examples/python-r4-us-core/fhir_types/profile_helpers.py
@@ -444,6 +444,29 @@ def validate_slice_cardinality(
     return errors
 
 
+def validate_slice_fields(
+    res: object,
+    profile_name: str,
+    field: str,
+    match: Mapping[str, Any],
+    slice_name: str,
+    required_fields: Sequence[str],
+) -> list[str]:
+    """Validates required fields within matched slice elements. For each array
+    item matching the discriminator, checks that the listed fields are present."""
+    items = _get_field(res, field) or []
+    if not isinstance(items, Iterable):
+        items = []
+    errors: list[str] = []
+    for item in items:
+        if not matches_value(item, match):
+            continue
+        for rf in required_fields:
+            if _get_field(item, rf) is None:
+                errors.append(f"{profile_name}.{field}[{slice_name}].{rf} is required")
+    return errors
+
+
 def validate_choice_required(res: object, profile_name: str, choices: Sequence[str]) -> list[str]:
     """Checks that at least one of the listed choice-type variants is present."""
     if any(_get_field(res, c) is not None for c in choices):
@@ -451,6 +474,17 @@ def validate_choice_required(res: object, profile_name: str, choices: Sequence[s
     return [f"{profile_name}: at least one of {', '.join(choices)} is required"]
 
 
+def validate_choice_prohibited(res: object, profile_name: str, prohibited: Sequence[str]) -> list[str]:
+    """Checks that none of the listed prohibited choice-type variants is present.
+    E.g. a profile narrowing ``value[x]`` to ``value_quantity`` prohibits every
+    other variant."""
+    return [
+        f"{profile_name}: field '{c}' must not be present"
+        for c in prohibited
+        if _get_field(res, c) is not None
+    ]
+
+
 def validate_enum(res: object, profile_name: str, field: str, allowed: Sequence[str]) -> list[str]:
     """Checks that the value of ``field`` has a code within ``allowed``.
     Handles plain strings, Coding, and CodeableConcept."""
diff --git a/examples/python-r4-us-core/test_profile_bp.py b/examples/python-r4-us-core/test_profile_bp.py
index 4b4f337f..25e094cb 100644
--- a/examples/python-r4-us-core/test_profile_bp.py
+++ b/examples/python-r4-us-core/test_profile_bp.py
@@ -116,6 +116,8 @@ def test_freshly_created_profile_is_not_yet_valid_missing_effective() -> None:
     errors = profile.validate()["errors"]
     assert errors == [
         "UscoreBloodPressureProfile: at least one of effectiveDateTime, effectivePeriod is required",
+        "UscoreBloodPressureProfile.component[systolic].valueQuantity is required",
+        "UscoreBloodPressureProfile.component[diastolic].valueQuantity is required",
     ]
 
 
diff --git a/src/api/writer-generator/python/naming-utils.ts b/src/api/writer-generator/python/naming-utils.ts
index 6decb290..fe5f26c3 100644
--- a/src/api/writer-generator/python/naming-utils.ts
+++ b/src/api/writer-generator/python/naming-utils.ts
@@ -1,4 +1,6 @@
 import { pascalCase, snakeCase, uppercaseFirstLetterOfEach } from "@root/api/writer-generator/utils";
+import type { TypeSchemaIndex } from "@root/typeschema/utils";
+import type { ChoiceFieldInstance, RegularField } from "@typeschema/types.ts";
 import { isPrimitiveIdentifier, type TypeIdentifier } from "@typeschema/types.ts";
 
 export const PRIMITIVE_TYPE_MAP: Record<string, string> = {
@@ -121,3 +123,23 @@ export const pyTypeFromIdentifier = (id: TypeIdentifier): string => {
     if (prim !== undefined) return prim;
     return deriveResourceName(id);
 };
+
+/** `Literal[...]` type argument for a `Reference` field's targets, mirroring
+ *  the TypeScript writer's `Reference<"Patient" | ...>`. Returns undefined
+ *  when there are no targets or a target is a family type (e.g. `Resource`),
+ *  where the bare `Reference` (defaulting to `str`) is the right annotation. */
+export const pyReferenceTypeParam = (
+    field: RegularField | ChoiceFieldInstance,
+    tsIndex: TypeSchemaIndex,
+): string | undefined => {
+    if (!field.reference || field.reference.resource.length === 0) return undefined;
+    const isFamilyType = (ref: TypeIdentifier): boolean => {
+        const schema = tsIndex.resolveType(ref);
+        if (!schema || !("typeFamily" in schema)) return false;
+        return (schema.typeFamily?.resources?.length ?? 0) > 0;
+    };
+    const resolved = field.reference.resource.map((ref) => tsIndex.findLastSpecializationByIdentifier(ref));
+    if (resolved.some(isFamilyType)) return undefined;
+    const names = [...new Set(resolved.map((ref) => ref.name))];
+    return `Literal[${names.map((n) => JSON.stringify(n)).join(", ")}]`;
+};
diff --git a/src/api/writer-generator/python/profile-factory.ts b/src/api/writer-generator/python/profile-factory.ts
index 1e04370d..b7ca5f40 100644
--- a/src/api/writer-generator/python/profile-factory.ts
+++ b/src/api/writer-generator/python/profile-factory.ts
@@ -10,7 +10,7 @@ import {
     type TypeIdentifier,
 } from "@root/typeschema/types";
 import type { TypeSchemaIndex } from "@root/typeschema/utils";
-import { pyTypeFromIdentifier } from "./naming-utils";
+import { pyReferenceTypeParam, pyTypeFromIdentifier } from "./naming-utils";
 import { pyFieldName, pySliceStaticName, pySnakeName } from "./profile-naming";
 import { collectRequiredSliceNames } from "./profile-slices";
 import type { Python } from "./writer";
@@ -22,8 +22,14 @@ import type { Python } from "./writer";
 export type ProfileFactoryInfo = {
     autoFields: { name: string; value: string }[];
     sliceAutoFields: { name: string; pyType: string; typeId: TypeIdentifier; sliceNames: string[] }[];
-    params: { name: string; pyType: string; typeId: TypeIdentifier }[];
-    accessors: { name: string; pyType: string; typeId: TypeIdentifier; choiceSiblings?: string[] }[];
+    params: { name: string; pyType: string; typeId: TypeIdentifier; refComment?: string }[];
+    accessors: {
+        name: string;
+        pyType: string;
+        typeId: TypeIdentifier;
+        choiceSiblings?: string[];
+        refComment?: string;
+    }[];
 };
 
 // ---------------------------------------------------------------------------
@@ -38,16 +44,29 @@ export type ProfileFactoryInfo = {
 export const fieldPyType = (
     field: RegularField | ChoiceFieldInstance,
     resolveRef?: TypeSchemaIndex["findLastSpecializationByIdentifier"],
+    tsIndex?: TypeSchemaIndex,
 ): string => {
     const resolved = resolveRef ? resolveRef(field.type) : field.type;
-    const base = pyTypeFromIdentifier(resolved);
+    let base = pyTypeFromIdentifier(resolved);
     if (base === "str" && field.enum && !field.enum.isOpen && field.enum.values.length > 0) {
         const literal = `Literal[${field.enum.values.map((v) => JSON.stringify(v)).join(", ")}]`;
         return field.array ? `list[${literal}]` : literal;
     }
+    if (base === "Reference" && tsIndex) {
+        const typeParam = pyReferenceTypeParam(field, tsIndex);
+        if (typeParam) base = `Reference[${typeParam}]`;
+    }
     return field.array ? `list[${base}]` : base;
 };
 
+/** Trailing `#` comment with the profile URLs of a reference field's targets.
+ *  Profile targets are replaced by their base resource type in the annotation;
+ *  the URLs are kept here to make server-side validation errors traceable. */
+export const pyReferenceComment = (field: RegularField | ChoiceFieldInstance): string | undefined => {
+    const urls = (field.reference?.profiles ?? []).map((profile) => profile.url);
+    return urls.length > 0 ? `  # ${urls.join(", ")}` : undefined;
+};
+
 // ---------------------------------------------------------------------------
 // Factory info collection
 // ---------------------------------------------------------------------------
@@ -58,17 +77,33 @@ const tryPromoteChoice = (
     fields: Record<string, Field>,
     params: ProfileFactoryInfo["params"],
     promotedChoices: Set<string>,
+    tsIndex: TypeSchemaIndex,
 ): void => {
     if (!isChoiceDeclarationField(field) || !field.required || field.choices.length !== 1) return;
     const choiceName = field.choices[0];
     if (!choiceName) return;
     const choiceField = fields[choiceName];
     if (!choiceField || !isChoiceInstanceField(choiceField)) return;
-    const pyType = pyTypeFromIdentifier(choiceField.type) + (choiceField.array ? "[]" : "");
-    params.push({ name: choiceName, pyType, typeId: choiceField.type });
+    const pyType = pyChoiceInstanceType(choiceField, tsIndex);
+    params.push({
+        name: choiceName,
+        pyType,
+        typeId: choiceField.type,
+        refComment: pyReferenceComment(choiceField),
+    });
     promotedChoices.add(choiceName);
 };
 
+/** Python type for a choice variant, with Reference targets parametrized. */
+const pyChoiceInstanceType = (field: ChoiceFieldInstance, tsIndex: TypeSchemaIndex): string => {
+    let base = pyTypeFromIdentifier(field.type);
+    if (base === "Reference") {
+        const typeParam = pyReferenceTypeParam(field, tsIndex);
+        if (typeParam) base = `Reference[${typeParam}]`;
+    }
+    return base + (field.array ? "[]" : "");
+};
+
 /** Include base-type required fields not already covered by profile constraints. */
 const collectBaseRequiredParams = (
     tsIndex: TypeSchemaIndex,
@@ -86,8 +121,8 @@ const collectBaseRequiredParams = (
         if (isChoiceInstanceField(field)) continue;
         if (isChoiceDeclarationField(field)) continue;
         if (isNotChoiceDeclarationField(field) && field.type) {
-            const pyType = fieldPyType(field, resolveRef);
-            params.push({ name, pyType, typeId: field.type });
+            const pyType = fieldPyType(field, resolveRef, tsIndex);
+            params.push({ name, pyType, typeId: field.type, refComment: pyReferenceComment(field) });
         }
     }
 };
@@ -124,7 +159,7 @@ export const collectProfileFactoryInfo = (
         }
 
         if (isChoiceDeclarationField(field)) {
-            tryPromoteChoice(field, fields, params, promotedChoices);
+            tryPromoteChoice(field, fields, params, promotedChoices, tsIndex);
             continue;
         }
 
@@ -132,8 +167,8 @@ export const collectProfileFactoryInfo = (
             const value = JSON.stringify(field.valueConstraint.value);
             autoFields.push({ name, value: field.array ? `[${value}]` : value });
             if (isNotChoiceDeclarationField(field) && field.type) {
-                const pyType = fieldPyType(field, resolveRef);
-                autoAccessors.push({ name, pyType, typeId: field.type });
+                const pyType = fieldPyType(field, resolveRef, tsIndex);
+                autoAccessors.push({ name, pyType, typeId: field.type, refComment: pyReferenceComment(field) });
             }
             continue;
         }
@@ -142,17 +177,17 @@ export const collectProfileFactoryInfo = (
             const sliceNames = collectRequiredSliceNames(field);
             if (sliceNames) {
                 if (field.type) {
-                    const pyType = fieldPyType(field, resolveRef);
+                    const pyType = fieldPyType(field, resolveRef, tsIndex);
                     sliceAutoFields.push({ name, pyType, typeId: field.type, sliceNames });
-                    autoAccessors.push({ name, pyType, typeId: field.type });
+                    autoAccessors.push({ name, pyType, typeId: field.type, refComment: pyReferenceComment(field) });
                 }
                 continue;
             }
         }
 
         if (field.required) {
-            const pyType = fieldPyType(field, resolveRef);
-            params.push({ name, pyType, typeId: field.type });
+            const pyType = fieldPyType(field, resolveRef, tsIndex);
+            params.push({ name, pyType, typeId: field.type, refComment: pyReferenceComment(field) });
         }
     }
 
@@ -166,9 +201,15 @@ export const collectProfileFactoryInfo = (
     const choiceAccessors: ProfileFactoryInfo["accessors"] = [];
     for (const [name, field] of pendingChoiceInstances) {
         if (promotedChoices.has(name)) continue;
-        const pyType = pyTypeFromIdentifier(field.type) + (field.array ? "[]" : "");
+        const pyType = pyChoiceInstanceType(field, tsIndex);
         const choiceSiblings = (choiceGroups.get(name) ?? []).filter((s) => s !== name && !promotedChoices.has(s));
-        choiceAccessors.push({ name, pyType, typeId: field.type, choiceSiblings });
+        choiceAccessors.push({
+            name,
+            pyType,
+            typeId: field.type,
+            choiceSiblings,
+            refComment: pyReferenceComment(field),
+        });
     }
 
     return { autoFields, sliceAutoFields, params, accessors: [...autoAccessors, ...choiceAccessors] };
@@ -280,12 +321,12 @@ export const generateFieldAccessors = (
     for (const p of factoryInfo.params) {
         const fieldName = pyFieldName(p.name, fmt);
         const methodSuffix = pySnakeName(p.name);
-        w.line(`def get_${methodSuffix}(self) -> ${p.pyType} | None:`);
+        w.line(`def get_${methodSuffix}(self) -> ${p.pyType} | None:${p.refComment ?? ""}`);
         w.indentBlock(() => {
             w.line(`return cast('${p.pyType} | None', getattr(self._resource, ${JSON.stringify(fieldName)}, None))`);
         });
         w.line();
-        w.line(`def set_${methodSuffix}(self, value: ${p.pyType}) -> "${className}":`);
+        w.line(`def set_${methodSuffix}(self, value: ${p.pyType}) -> "${className}":${p.refComment ?? ""}`);
         w.indentBlock(() => {
             w.line(`setattr(self._resource, ${JSON.stringify(fieldName)}, value)`);
             w.line("return self");
@@ -297,12 +338,12 @@ export const generateFieldAccessors = (
         const methodSuffix = pySnakeName(a.name);
         if (extSliceMethodBaseNames.has(methodSuffix)) continue;
         const fieldName = pyFieldName(a.name, fmt);
-        w.line(`def get_${methodSuffix}(self) -> ${a.pyType} | None:`);
+        w.line(`def get_${methodSuffix}(self) -> ${a.pyType} | None:${a.refComment ?? ""}`);
         w.indentBlock(() => {
             w.line(`return cast('${a.pyType} | None', getattr(self._resource, ${JSON.stringify(fieldName)}, None))`);
         });
         w.line();
-        w.line(`def set_${methodSuffix}(self, value: ${a.pyType}) -> "${className}":`);
+        w.line(`def set_${methodSuffix}(self, value: ${a.pyType}) -> "${className}":${a.refComment ?? ""}`);
         w.indentBlock(() => {
             if (a.choiceSiblings?.length) {
                 for (const sibling of a.choiceSiblings) {
diff --git a/src/api/writer-generator/python/profile-validation.ts b/src/api/writer-generator/python/profile-validation.ts
index 6e4b8004..d00e5885 100644
--- a/src/api/writer-generator/python/profile-validation.ts
+++ b/src/api/writer-generator/python/profile-validation.ts
@@ -1,6 +1,5 @@
 import {
     type ChoiceFieldInstance,
-    type Field,
     isChoiceDeclarationField,
     isChoiceInstanceField,
     isNotChoiceDeclarationField,
@@ -14,11 +13,29 @@ import { pyFieldName } from "./profile-naming";
 // Validation body collection
 // ---------------------------------------------------------------------------
 
+/** Emit `<target>.extend(<fn>(self._resource, profile_name, <args>, [<items>]))`
+ *  with the call and its trailing list argument split across lines:
+ *
+ *      errors.extend(
+ *          validate_enum(self._resource, profile_name, "code", [
+ *              "85353-1","9279-1",...
+ *      ]))
+ */
+const pushListValidation = (lines: string[], target: string, fn: string, args: string[], items: string[]): void => {
+    const argList = ["self._resource", "profile_name", ...args].join(", ");
+    lines.push(
+        `${target}.extend(`,
+        `    ${fn}(${argList}, [`,
+        `        ${items.map((i) => JSON.stringify(i)).join(",")}`,
+        "]))",
+    );
+};
+
 /** Walk fields once and emit validate() body lines into `out`, returning the
  *  set of helper function names referenced. Pure: no writer side effects. */
 export const collectValidateBody = (
     flatProfile: SnapshotProfileTypeSchema,
-    resolveRef: TypeSchemaIndex["findLastSpecializationByIdentifier"],
+    tsIndex: TypeSchemaIndex,
     errorLines: string[],
     warningLines: string[],
     formatName: (s: string) => string,
@@ -27,101 +44,124 @@ export const collectValidateBody = (
     const fields = flatProfile.fields;
     for (const [name, field] of Object.entries(fields)) {
         const pyName = pyFieldName(name, formatName);
-        if (isChoiceInstanceField(field)) {
-            collectProhibitedChoiceValidation(fields, name, pyName, helpers, errorLines);
-            continue;
-        }
+        if (isChoiceInstanceField(field)) continue;
         if (isChoiceDeclarationField(field)) {
             if (field.required) {
                 helpers.add("validate_choice_required");
                 const pyChoices = field.choices.map((c) => pyFieldName(c, formatName));
-                errorLines.push(
-                    `errors.extend(validate_choice_required(self._resource, profile_name, ${JSON.stringify(pyChoices)}))`,
-                );
-            }
-            continue;
-        }
-        if (field.excluded) {
-            helpers.add("validate_excluded");
-            errorLines.push(
-                `errors.extend(validate_excluded(self._resource, profile_name, ${JSON.stringify(pyName)}))`,
-            );
-            continue;
-        }
-        if (field.required) {
-            helpers.add("validate_required");
-            errorLines.push(
-                `errors.extend(validate_required(self._resource, profile_name, ${JSON.stringify(pyName)}))`,
-            );
-        }
-        if (field.valueConstraint) {
-            helpers.add("validate_fixed_value");
-            const value = JSON.stringify(field.valueConstraint.value);
-            errorLines.push(
-                `errors.extend(validate_fixed_value(self._resource, profile_name, ${JSON.stringify(pyName)}, ${value}))`,
-            );
-        }
-        if (isNotChoiceDeclarationField(field)) {
-            if (field.enum) {
-                helpers.add("validate_enum");
-                const target = field.enum.isOpen ? warningLines : errorLines;
-                const listName = field.enum.isOpen ? "warnings" : "errors";
-                target.push(
-                    `${listName}.extend(validate_enum(self._resource, profile_name, ${JSON.stringify(pyName)}, ${JSON.stringify(field.enum.values)}))`,
-                );
-            }
-            if (field.mustSupport && !field.required) {
-                helpers.add("validate_must_support");
-                warningLines.push(
-                    `warnings.extend(validate_must_support(self._resource, profile_name, ${JSON.stringify(pyName)}))`,
-                );
+                pushListValidation(errorLines, "errors", "validate_choice_required", [], pyChoices);
             }
-            if (field.reference && field.reference.resource.length > 0) {
-                helpers.add("validate_reference");
-                const allowed = field.reference.resource.map((ref) => resolveRef(ref).name);
-                errorLines.push(
-                    `errors.extend(validate_reference(self._resource, profile_name, ${JSON.stringify(pyName)}, ${JSON.stringify(allowed)}))`,
-                );
-            }
-            if (field.slicing?.slices) {
-                collectSliceCardinalityValidation(field, pyName, helpers, errorLines);
+            if (field.prohibited?.length) {
+                helpers.add("validate_choice_prohibited");
+                const pyProhibited = field.prohibited.map((c) => pyFieldName(c, formatName));
+                pushListValidation(errorLines, "errors", "validate_choice_prohibited", [], pyProhibited);
             }
+            continue;
         }
+        collectRegularFieldValidation(field, pyName, helpers, errorLines, warningLines, tsIndex, formatName);
+    }
+    // Base-resource required fields the profile chain did not re-state.
+    // Emitted here (not via the regular field loop) because they intentionally
+    // live outside `fields` to avoid pulling unrelated base metadata into the
+    // profile's getter/setter surface.
+    for (const inheritedName of flatProfile.inheritedRequiredFields ?? []) {
+        helpers.add("validate_required");
+        errorLines.push(
+            `errors.extend(validate_required(self._resource, profile_name, ${JSON.stringify(pyFieldName(inheritedName, formatName))}))`,
+        );
     }
     return helpers;
 };
 
-const collectProhibitedChoiceValidation = (
-    fields: Record<string, Field>,
-    name: string,
+const collectRegularFieldValidation = (
+    field: RegularField | ChoiceFieldInstance,
     pyName: string,
     helpers: Set<string>,
     errorLines: string[],
+    warningLines: string[],
+    tsIndex: TypeSchemaIndex,
+    formatName: (s: string) => string,
 ): void => {
-    const field = fields[name];
-    if (!field || !isChoiceInstanceField(field)) return;
-    const decl = fields[field.choiceOf];
-    if (!decl || !isChoiceDeclarationField(decl) || !decl.prohibited?.includes(name)) return;
-    helpers.add("validate_excluded");
-    errorLines.push(`errors.extend(validate_excluded(self._resource, profile_name, ${JSON.stringify(pyName)}))`);
+    if (field.excluded) {
+        helpers.add("validate_excluded");
+        errorLines.push(`errors.extend(validate_excluded(self._resource, profile_name, ${JSON.stringify(pyName)}))`);
+        return;
+    }
+    if (field.required) {
+        helpers.add("validate_required");
+        errorLines.push(`errors.extend(validate_required(self._resource, profile_name, ${JSON.stringify(pyName)}))`);
+    }
+    if (field.valueConstraint) {
+        helpers.add("validate_fixed_value");
+        const value = JSON.stringify(field.valueConstraint.value);
+        errorLines.push(
+            `errors.extend(validate_fixed_value(self._resource, profile_name, ${JSON.stringify(pyName)}, ${value}))`,
+        );
+    }
+    if (isNotChoiceDeclarationField(field)) {
+        if (field.enum) {
+            helpers.add("validate_enum");
+            const target = field.enum.isOpen ? warningLines : errorLines;
+            const listName = field.enum.isOpen ? "warnings" : "errors";
+            pushListValidation(target, listName, "validate_enum", [JSON.stringify(pyName)], field.enum.values);
+        }
+        if (field.mustSupport && !field.required) {
+            helpers.add("validate_must_support");
+            warningLines.push(
+                `warnings.extend(validate_must_support(self._resource, profile_name, ${JSON.stringify(pyName)}))`,
+            );
+        }
+        if (field.reference && field.reference.resource.length > 0) {
+            helpers.add("validate_reference");
+            const allowed = field.reference.resource.map((ref) => tsIndex.findLastSpecializationByIdentifier(ref).name);
+            pushListValidation(errorLines, "errors", "validate_reference", [JSON.stringify(pyName)], allowed);
+        }
+        if (field.slicing?.slices) {
+            collectSliceValidation(field, pyName, helpers, errorLines, tsIndex, formatName);
+        }
+    }
 };
 
-const collectSliceCardinalityValidation = (
+const collectSliceValidation = (
     field: RegularField | ChoiceFieldInstance,
     name: string,
     helpers: Set<string>,
     errorLines: string[],
+    tsIndex: TypeSchemaIndex,
+    formatName: (s: string) => string,
 ): void => {
     if (!field.slicing?.slices) return;
     for (const [sliceName, slice] of Object.entries(field.slicing.slices)) {
-        if (slice.min === undefined && slice.max === undefined) continue;
         const match = slice.match ?? {};
         if (Object.keys(match).length === 0) continue;
-        const min = slice.min ?? 0;
-        const max = slice.max ?? 0;
-        helpers.add("validate_slice_cardinality");
-        errorLines.push(
-            `errors.extend(validate_slice_cardinality(self._resource, profile_name, ${JSON.stringify(name)}, ${JSON.stringify(match)}, ${JSON.stringify(sliceName)}, ${min}, ${max}))`,
-        );
+        if (slice.min !== undefined || slice.max !== undefined) {
+            const min = slice.min ?? 0;
+            const max = slice.max ?? 0;
+            helpers.add("validate_slice_cardinality");
+            errorLines.push(
+                `errors.extend(validate_slice_cardinality(self._resource, profile_name, ${JSON.stringify(name)}, ${JSON.stringify(match)}, ${JSON.stringify(sliceName)}, ${min}, ${max}))`,
+            );
+        }
+        // Collect required fields within the slice element
+        const sliceRequiredFields: string[] = [];
+        const matchKeys = new Set(Object.keys(match));
+        for (const rf of slice.required ?? []) {
+            if (!matchKeys.has(rf)) sliceRequiredFields.push(pyFieldName(rf, formatName));
+        }
+        // Constrained choice: the single variant is required
+        if (field.type && slice.elements) {
+            const cc = tsIndex.constrainedChoice(field.type.package, field.type, slice.elements);
+            if (cc) sliceRequiredFields.push(pyFieldName(cc.variant, formatName));
+        }
+        if (sliceRequiredFields.length > 0) {
+            helpers.add("validate_slice_fields");
+            pushListValidation(
+                errorLines,
+                "errors",
+                "validate_slice_fields",
+                [JSON.stringify(name), JSON.stringify(match), JSON.stringify(sliceName)],
+                sliceRequiredFields,
+            );
+        }
     }
 };
diff --git a/src/api/writer-generator/python/profile.ts b/src/api/writer-generator/python/profile.ts
index 8b4b943f..11054591 100644
--- a/src/api/writer-generator/python/profile.ts
+++ b/src/api/writer-generator/python/profile.ts
@@ -403,13 +403,7 @@ const generateProfileModule = (w: Python, tsIndex: TypeSchemaIndex, flatProfile:
     const resolvedNames = resolveProfileMethodBaseNames(extensions, sliceDefs);
     const errorLines: string[] = [];
     const warningLines: string[] = [];
-    const validationHelpers = collectValidateBody(
-        flatProfile,
-        tsIndex.findLastSpecializationByIdentifier,
-        errorLines,
-        warningLines,
-        w.nameFormatFunction,
-    );
+    const validationHelpers = collectValidateBody(flatProfile, tsIndex, errorLines, warningLines, w.nameFormatFunction);
 
     const helperImports = collectHelperImports(isResourceBase, factoryInfo, sliceDefs, extensions, validationHelpers);
     const typeImports = collectTypeImports(
diff --git a/src/api/writer-generator/python/writer.ts b/src/api/writer-generator/python/writer.ts
index bb8e4a9c..3ed991cb 100644
--- a/src/api/writer-generator/python/writer.ts
+++ b/src/api/writer-generator/python/writer.ts
@@ -24,6 +24,7 @@ import {
     type SpecializationTypeSchema,
     type TypeIdentifier,
 } from "@typeschema/types.ts";
+import { pyReferenceTypeParam } from "./naming-utils";
 import { generateNewProfiles } from "./profile";
 
 export const resolvePyAssets = (fn: string) => {
@@ -48,6 +49,7 @@ const MAX_IMPORT_LINE_LENGTH = 100;
 const GENERIC_FIELD_REWRITES: Record<string, Record<string, string>> = {
     Coding: { code: "T" },
     CodeableConcept: { coding: "Coding[T]" },
+    Reference: { type: "T" },
 };
 
 const leafOf = (path: string[]): string => path[path.length - 1] ?? "";
@@ -590,6 +592,12 @@ export class Python extends Writer<PythonGeneratorOptions> {
             }
         }
 
+        if (fieldType === "Reference" && "reference" in field && field.reference) {
+            assert(this.tsIndex !== undefined);
+            const typeParam = pyReferenceTypeParam(field, this.tsIndex);
+            if (typeParam) fieldType = `Reference[${typeParam}]`;
+        }
+
         if (field.array) {
             fieldType = `PyList[${fieldType}]`;
         }
diff --git a/test/api/write-generator/__snapshots__/python.test.ts.snap b/test/api/write-generator/__snapshots__/python.test.ts.snap
index 895f7062..98e4389a 100644
--- a/test/api/write-generator/__snapshots__/python.test.ts.snap
+++ b/test/api/write-generator/__snapshots__/python.test.ts.snap
@@ -144,14 +144,14 @@ class PatientContact(BackboneElement):
     address: Address | None = Field(None, alias="address", serialization_alias="address")
     gender: Literal["male", "female", "other", "unknown"] | None = Field(None, alias="gender", serialization_alias="gender")
     name: HumanName | None = Field(None, alias="name", serialization_alias="name")
-    organization: Reference | None = Field(None, alias="organization", serialization_alias="organization")
+    organization: Reference[Literal["Organization"]] | None = Field(None, alias="organization", serialization_alias="organization")
     period: Period | None = Field(None, alias="period", serialization_alias="period")
     relationship: PyList[CodeableConcept] | None = Field(None, alias="relationship", serialization_alias="relationship")
     telecom: PyList[ContactPoint] | None = Field(None, alias="telecom", serialization_alias="telecom")
 
 class PatientLink(BackboneElement):
     model_config = ConfigDict(validate_by_name=True, serialize_by_alias=True, extra="forbid")
-    other: Reference = Field(alias="other", serialization_alias="other")
+    other: Reference[Literal["Patient", "RelatedPerson"]] = Field(alias="other", serialization_alias="other")
     type: Literal["replaced-by", "replaces", "refer", "seealso"] = Field(alias="type", serialization_alias="type")
 
 
@@ -172,10 +172,10 @@ class Patient(DomainResource):
     deceasedBoolean: bool | None = Field(None, alias="deceasedBoolean", serialization_alias="deceasedBoolean")
     deceasedDateTime: str | None = Field(None, alias="deceasedDateTime", serialization_alias="deceasedDateTime")
     gender: Literal["male", "female", "other", "unknown"] | None = Field(None, alias="gender", serialization_alias="gender")
-    generalPractitioner: PyList[Reference] | None = Field(None, alias="generalPractitioner", serialization_alias="generalPractitioner")
+    generalPractitioner: PyList[Reference[Literal["Organization", "Practitioner", "PractitionerRole"]]] | None = Field(None, alias="generalPractitioner", serialization_alias="generalPractitioner")
     identifier: PyList[Identifier] | None = Field(None, alias="identifier", serialization_alias="identifier")
     link: PyList[PatientLink] | None = Field(None, alias="link", serialization_alias="link")
-    managingOrganization: Reference | None = Field(None, alias="managingOrganization", serialization_alias="managingOrganization")
+    managingOrganization: Reference[Literal["Organization"]] | None = Field(None, alias="managingOrganization", serialization_alias="managingOrganization")
     maritalStatus: CodeableConcept[Literal["A", "D", "I", "L", "M", "P", "S", "T", "U", "W", "UNK"] | str] | None = Field(None, alias="maritalStatus", serialization_alias="maritalStatus")
     multipleBirthBoolean: bool | None = Field(None, alias="multipleBirthBoolean", serialization_alias="multipleBirthBoolean")
     multipleBirthInteger: int | None = Field(None, alias="multipleBirthInteger", serialization_alias="multipleBirthInteger")
@@ -423,8 +423,8 @@ from fhir_types.hl7_fhir_r4_core.observation import Observation
 from fhir_types.hl7_fhir_r4_core.base import CodeableConcept, Period, Quantity, Reference
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \\
-    set_array_slice, strip_match_keys, validate_choice_required, validate_enum, validate_fixed_value, validate_must_support, \\
-    validate_reference, validate_required, validate_slice_cardinality
+    set_array_slice, strip_match_keys, validate_choice_prohibited, validate_choice_required, validate_enum, \\
+    validate_fixed_value, validate_must_support, validate_reference, validate_required, validate_slice_cardinality
 )
 
 
@@ -459,7 +459,7 @@ class ObservationBodyweightProfile:
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
 
         return build_resource(
@@ -473,7 +473,7 @@ class ObservationBodyweightProfile:
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> "ObservationBodyweightProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> "ObservationBodyweightProfile":
         return cls.apply(cls.create_resource(category=category, status=status, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -486,10 +486,10 @@ class ObservationBodyweightProfile:
         setattr(self._resource, "status", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "ObservationBodyweightProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "ObservationBodyweightProfile":
         setattr(self._resource, "subject", value)
         return self
 
@@ -556,19 +556,51 @@ class ObservationBodyweightProfile:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "code", {"coding":[{"code":"29463-7","system":"http://loinc.org"}]}))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["85353-1","9279-1","8867-4","2708-6","8310-5","8302-2","9843-4","29463-7","39156-5","85354-9","8480-6","8462-4","8478-0"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueCodeableConcept","valueString","valueBoolean","valueInteger","valueRange","valueRatio","valueSampledData","valueTime","valueDateTime","valuePeriod"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "85353-1","9279-1","8867-4","2708-6","8310-5","8302-2","9843-4","29463-7","39156-5","85354-9","8480-6","8462-4","8478-0"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         return {"errors": errors, "warnings": warnings}
 
@@ -591,8 +623,9 @@ from fhir_types.hl7_fhir_r4_core.base import (
 from fhir_types.hl7_fhir_r4_core.observation import ObservationComponent
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \\
-    set_array_slice, strip_match_keys, unwrap_slice_choice, validate_choice_required, validate_enum, validate_fixed_value, \\
-    validate_must_support, validate_reference, validate_required, validate_slice_cardinality, wrap_slice_choice
+    set_array_slice, strip_match_keys, unwrap_slice_choice, validate_choice_prohibited, validate_choice_required, \\
+    validate_enum, validate_fixed_value, validate_must_support, validate_reference, validate_required, validate_slice_cardinality, \\
+    validate_slice_fields, wrap_slice_choice
 )
 
 
@@ -629,7 +662,7 @@ class ObservationBpProfile:
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
         component_with_defaults = ensure_slice_defaults(
             list(component or []),
@@ -649,7 +682,7 @@ class ObservationBpProfile:
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> "ObservationBpProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> "ObservationBpProfile":
         return cls.apply(cls.create_resource(category=category, component=component, status=status, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -662,10 +695,10 @@ class ObservationBpProfile:
         setattr(self._resource, "status", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "ObservationBpProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "ObservationBpProfile":
         setattr(self._resource, "subject", value)
         return self
 
@@ -783,21 +816,61 @@ class ObservationBpProfile:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "code", {"coding":[{"code":"85354-9","system":"http://loinc.org"}]}))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"code":"8480-6","system":"http://loinc.org"}]}}, "SystolicBP", 1, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "component", {"code":{"coding":[{"code":"8480-6","system":"http://loinc.org"}]}}, "SystolicBP", [
+                "valueQuantity"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"code":"8462-4","system":"http://loinc.org"}]}}, "DiastolicBP", 1, 1))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["85353-1","9279-1","8867-4","2708-6","8310-5","8302-2","9843-4","29463-7","39156-5","85354-9","8480-6","8462-4","8478-0"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "component", {"code":{"coding":[{"code":"8462-4","system":"http://loinc.org"}]}}, "DiastolicBP", [
+                "valueQuantity"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueCodeableConcept","valueString","valueBoolean","valueInteger","valueRange","valueRatio","valueSampledData","valueTime","valueDateTime","valuePeriod"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "85353-1","9279-1","8867-4","2708-6","8310-5","8302-2","9843-4","29463-7","39156-5","85354-9","8480-6","8462-4","8478-0"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         return {"errors": errors, "warnings": warnings}
 
@@ -1087,8 +1160,9 @@ from fhir_types.hl7_fhir_r4_core.base import (
 from fhir_types.hl7_fhir_r4_core.observation import ObservationComponent
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \\
-    set_array_slice, strip_match_keys, unwrap_slice_choice, validate_choice_required, validate_enum, validate_fixed_value, \\
-    validate_must_support, validate_reference, validate_required, validate_slice_cardinality, wrap_slice_choice
+    set_array_slice, strip_match_keys, unwrap_slice_choice, validate_choice_prohibited, validate_choice_required, \\
+    validate_enum, validate_fixed_value, validate_must_support, validate_reference, validate_required, validate_slice_cardinality, \\
+    validate_slice_fields, wrap_slice_choice
 )
 
 
@@ -1125,7 +1199,7 @@ class UscoreBloodPressureProfile:
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
         component_with_defaults = ensure_slice_defaults(
             list(component or []),
@@ -1145,7 +1219,7 @@ class UscoreBloodPressureProfile:
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> "UscoreBloodPressureProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, component: list[BackboneElement] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> "UscoreBloodPressureProfile":
         return cls.apply(cls.create_resource(category=category, component=component, status=status, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -1158,10 +1232,10 @@ class UscoreBloodPressureProfile:
         setattr(self._resource, "status", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "UscoreBloodPressureProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "UscoreBloodPressureProfile":  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
         setattr(self._resource, "subject", value)
         return self
 
@@ -1459,22 +1533,61 @@ class UscoreBloodPressureProfile:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "code", {"coding":[{"system":"http://loinc.org","code":"85354-9"}]}))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8480-6"}]}}, "systolic", 1, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8480-6"}]}}, "systolic", [
+                "valueQuantity"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", 1, 1))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "component", {"code":{"coding":[{"system":"http://loinc.org","code":"8462-4"}]}}, "diastolic", [
+                "valueQuantity"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "performer", [
+                "PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         warnings.extend(validate_must_support(self._resource, profile_name, "performer"))
         return {"errors": errors, "warnings": warnings}
@@ -1497,8 +1610,8 @@ from fhir_types.hl7_fhir_r4_core.base import (
 )
 from fhir_types.profile_helpers import (
     apply_slice_match, build_resource, ensure_profile, ensure_slice_defaults, get_array_slice, matches_value, \\
-    set_array_slice, strip_match_keys, validate_choice_required, validate_enum, validate_excluded, validate_fixed_value, \\
-    validate_must_support, validate_reference, validate_required, validate_slice_cardinality
+    set_array_slice, strip_match_keys, validate_choice_prohibited, validate_choice_required, validate_enum, \\
+    validate_fixed_value, validate_must_support, validate_reference, validate_required, validate_slice_cardinality
 )
 
 
@@ -1533,7 +1646,7 @@ class UscoreBodyWeightProfile:
         return cls(resource)
 
     @classmethod
-    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> Observation:
+    def create_resource(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> Observation:
         category_with_defaults = ensure_slice_defaults(list(category or []), cls._vscat_slice_match)
 
         return build_resource(
@@ -1547,7 +1660,7 @@ class UscoreBodyWeightProfile:
         )
 
     @classmethod
-    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference) -> "UscoreBodyWeightProfile":
+    def create(cls, *, category: list[CodeableConcept] | None = None, status: Literal["registered", "preliminary", "final", "amended", "corrected", "cancelled", "entered-in-error", "unknown"], subject: Reference[Literal["Patient"]]) -> "UscoreBodyWeightProfile":
         return cls.apply(cls.create_resource(category=category, status=status, subject=subject))
 
     def to_resource(self) -> Observation:
@@ -1560,10 +1673,10 @@ class UscoreBodyWeightProfile:
         setattr(self._resource, "status", value)
         return self
 
-    def get_subject(self) -> Reference | None:
-        return cast('Reference | None', getattr(self._resource, "subject", None))
+    def get_subject(self) -> Reference[Literal["Patient"]] | None:  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
+        return cast('Reference[Literal["Patient"]] | None', getattr(self._resource, "subject", None))
 
-    def set_subject(self, value: Reference) -> "UscoreBodyWeightProfile":
+    def set_subject(self, value: Reference[Literal["Patient"]]) -> "UscoreBodyWeightProfile":  # http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient
         setattr(self._resource, "subject", value)
         return self
 
@@ -1700,30 +1813,55 @@ class UscoreBodyWeightProfile:
         errors: list[str] = []
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "status"))
-        errors.extend(validate_enum(self._resource, profile_name, "status", ["registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"]))
+        errors.extend(
+            validate_enum(self._resource, profile_name, "status", [
+                "registered","preliminary","final","amended","corrected","cancelled","entered-in-error","unknown"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "category"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "category", {"coding":[{"code":"vital-signs","system":"http://terminology.hl7.org/CodeSystem/observation-category"}]}, "VSCat", 1, 1))
         errors.extend(validate_required(self._resource, profile_name, "code"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "code", {"coding":[{"system":"http://loinc.org","code":"29463-7"}]}))
         errors.extend(validate_required(self._resource, profile_name, "subject"))
-        errors.extend(validate_reference(self._resource, profile_name, "subject", ["Patient"]))
-        errors.extend(validate_choice_required(self._resource, profile_name, ["effectiveDateTime","effectivePeriod"]))
-        errors.extend(validate_reference(self._resource, profile_name, "hasMember", ["MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "derivedFrom", ["DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"]))
-        errors.extend(validate_reference(self._resource, profile_name, "performer", ["PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"]))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueCodeableConcept"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueString"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueBoolean"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueInteger"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueRange"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueRatio"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueSampledData"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueTime"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valueDateTime"))
-        errors.extend(validate_excluded(self._resource, profile_name, "valuePeriod"))
-        warnings.extend(validate_enum(self._resource, profile_name, "category", ["social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "code", ["2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"]))
-        warnings.extend(validate_enum(self._resource, profile_name, "dataAbsentReason", ["unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "subject", [
+                "Patient"
+        ]))
+        errors.extend(
+            validate_choice_required(self._resource, profile_name, [
+                "effectiveDateTime","effectivePeriod"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "effectiveTiming","effectiveInstant"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "hasMember", [
+                "MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "derivedFrom", [
+                "DocumentReference","ImagingStudy","Media","MolecularSequence","QuestionnaireResponse","Observation"
+        ]))
+        errors.extend(
+            validate_reference(self._resource, profile_name, "performer", [
+                "PractitionerRole","CareTeam","Organization","Patient","Practitioner","RelatedPerson"
+        ]))
+        errors.extend(
+            validate_choice_prohibited(self._resource, profile_name, [
+                "valueCodeableConcept","valueString","valueBoolean","valueInteger","valueRange","valueRatio","valueSampledData","valueTime","valueDateTime","valuePeriod"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "category", [
+                "social-history","vital-signs","imaging","laboratory","procedure","survey","exam","therapy","activity"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "code", [
+                "2708-6","29463-7","3140-1","3150-0","3151-8","39156-5","59408-5","59575-1","59576-9","77606-2","8287-5","8289-1","8302-2","8306-3","8310-5","8462-4","8478-0","8480-6","8867-4","9279-1","9843-4"
+        ]))
+        warnings.extend(
+            validate_enum(self._resource, profile_name, "dataAbsentReason", [
+                "unknown","asked-unknown","temp-unknown","not-asked","asked-declined","masked","not-applicable","unsupported","as-text","error","not-a-number","negative-infinity","positive-infinity","not-performed","not-permitted"
+        ]))
         warnings.extend(validate_must_support(self._resource, profile_name, "dataAbsentReason"))
         warnings.extend(validate_must_support(self._resource, profile_name, "performer"))
         return {"errors": errors, "warnings": warnings}
@@ -1745,7 +1883,7 @@ from fhir_types.hl7_fhir_r4_core.base import Extension
 from fhir_types.profile_helpers import (
     _get_key, apply_slice_match, build_resource, ensure_slice_defaults, get_array_slice, get_extension_value, \\
     is_extension, is_record, matches_value, push_extension, set_array_slice, strip_match_keys, unwrap_slice_choice, \\
-    validate_fixed_value, validate_required, validate_slice_cardinality, wrap_slice_choice
+    validate_fixed_value, validate_required, validate_slice_cardinality, validate_slice_fields, wrap_slice_choice
 )
 
 
@@ -1952,7 +2090,19 @@ class UscoreRaceExtension:
         warnings: list[str] = []
         errors.extend(validate_required(self._resource, profile_name, "extension"))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "extension", {"url":"ombCategory"}, "ombCategory", 0, 6))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"ombCategory"}, "ombCategory", [
+                "value","valueCoding"
+        ]))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"detailed"}, "detailed", [
+                "value","valueCoding"
+        ]))
         errors.extend(validate_slice_cardinality(self._resource, profile_name, "extension", {"url":"text"}, "text", 1, 1))
+        errors.extend(
+            validate_slice_fields(self._resource, profile_name, "extension", {"url":"text"}, "text", [
+                "value","valueString"
+        ]))
         errors.extend(validate_required(self._resource, profile_name, "url"))
         errors.extend(validate_fixed_value(self._resource, profile_name, "url", "http://hl7.org/fhir/us/core/StructureDefinition/us-core-race"))
         return {"errors": errors, "warnings": warnings}
diff --git a/test/api/write-generator/multi-package/__snapshots__/local-package.test.ts.snap b/test/api/write-generator/multi-package/__snapshots__/local-package.test.ts.snap
index 94a6b778..fdb15d85 100644
--- a/test/api/write-generator/multi-package/__snapshots__/local-package.test.ts.snap
+++ b/test/api/write-generator/multi-package/__snapshots__/local-package.test.ts.snap
@@ -217,7 +217,7 @@ class ExampleNotebook(DomainResource):
         serialization_alias='resourceType',
         pattern='ExampleNotebook'
     )
-    author: Reference = Field(alias="author", serialization_alias="author")
+    author: Reference[Literal["Patient", "Practitioner"]] = Field(alias="author", serialization_alias="author")
     content: str = Field(alias="content", serialization_alias="content")
     identifier: Identifier = Field(alias="identifier", serialization_alias="identifier")
     tag: PyList[Coding] | None = Field(None, alias="tag", serialization_alias="tag")
@@ -313,14 +313,14 @@ class PatientContact(BackboneElement):
     address: Address | None = Field(None, alias="address", serialization_alias="address")
     gender: Literal["male", "female", "other", "unknown"] | None = Field(None, alias="gender", serialization_alias="gender")
     name: HumanName | None = Field(None, alias="name", serialization_alias="name")
-    organization: Reference | None = Field(None, alias="organization", serialization_alias="organization")
+    organization: Reference[Literal["Organization"]] | None = Field(None, alias="organization", serialization_alias="organization")
     period: Period | None = Field(None, alias="period", serialization_alias="period")
     relationship: PyList[CodeableConcept] | None = Field(None, alias="relationship", serialization_alias="relationship")
     telecom: PyList[ContactPoint] | None = Field(None, alias="telecom", serialization_alias="telecom")
 
 class PatientLink(BackboneElement):
     model_config = ConfigDict(validate_by_name=True, serialize_by_alias=True, extra="forbid")
-    other: Reference = Field(alias="other", serialization_alias="other")
+    other: Reference[Literal["Patient", "RelatedPerson"]] = Field(alias="other", serialization_alias="other")
     type: Literal["replaced-by", "replaces", "refer", "seealso"] = Field(alias="type", serialization_alias="type")
 
 
@@ -340,10 +340,10 @@ class Patient(DomainResource):
     deceasedBoolean: bool | None = Field(None, alias="deceasedBoolean", serialization_alias="deceasedBoolean")
     deceasedDateTime: str | None = Field(None, alias="deceasedDateTime", serialization_alias="deceasedDateTime")
     gender: Literal["male", "female", "other", "unknown"] | None = Field(None, alias="gender", serialization_alias="gender")
-    generalPractitioner: PyList[Reference] | None = Field(None, alias="generalPractitioner", serialization_alias="generalPractitioner")
+    generalPractitioner: PyList[Reference[Literal["Organization", "Practitioner", "PractitionerRole"]]] | None = Field(None, alias="generalPractitioner", serialization_alias="generalPractitioner")
     identifier: PyList[Identifier] | None = Field(None, alias="identifier", serialization_alias="identifier")
     link: PyList[PatientLink] | None = Field(None, alias="link", serialization_alias="link")
-    managingOrganization: Reference | None = Field(None, alias="managingOrganization", serialization_alias="managingOrganization")
+    managingOrganization: Reference[Literal["Organization"]] | None = Field(None, alias="managingOrganization", serialization_alias="managingOrganization")
     maritalStatus: CodeableConcept[Literal["A", "D", "I", "L", "M", "P", "S", "T", "U", "W", "UNK"] | str] | None = Field(None, alias="maritalStatus", serialization_alias="maritalStatus")
     multipleBirthBoolean: bool | None = Field(None, alias="multipleBirthBoolean", serialization_alias="multipleBirthBoolean")
     multipleBirthInteger: int | None = Field(None, alias="multipleBirthInteger", serialization_alias="multipleBirthInteger")
diff --git a/test/api/write-generator/profile-inherited-required.test.ts b/test/api/write-generator/profile-inherited-required.test.ts
index 4f1674e7..ce4cbf24 100644
--- a/test/api/write-generator/profile-inherited-required.test.ts
+++ b/test/api/write-generator/profile-inherited-required.test.ts
@@ -72,3 +72,41 @@ describe("Profile inherited base-required fields (codegen-8iw)", async () => {
         expect(file).toMatch(/import\s*\{[^}]*\bvalidateRequired\b/);
     });
 });
+
+describe("Profile inherited base-required fields, Python writer (codegen-8iw)", async () => {
+    const result = await new APIBuilder({ logger: mkSilentLogger() })
+        .localStructureDefinitions({
+            package: { name: "cognovis.test.praxis", version: "0.0.1" },
+            path: FIXTURE_PATH,
+            dependencies: [{ name: "hl7.fhir.r4.core", version: "4.0.1" }],
+        })
+        .python({ inMemoryOnly: true, generateProfile: true, client: "none" })
+        .generate();
+
+    const profileKey = Object.keys(result.filesGenerated.python ?? {}).find((k) =>
+        k.includes("provenance_praxis_proposal_provenance"),
+    );
+    const profileFile = () => (profileKey ? result.filesGenerated.python![profileKey] : undefined);
+
+    it("should succeed", () => {
+        expect(result.success).toBeTrue();
+    });
+
+    it("generates the Provenance profile class", () => {
+        expect(profileKey).toBeDefined();
+    });
+
+    it("emits validate_required() for the differential-stated required fields", () => {
+        const file = profileFile();
+        expect(file).toBeDefined();
+        expect(file).toContain('validate_required(self._resource, profile_name, "activity")');
+        expect(file).toContain('validate_required(self._resource, profile_name, "agent")');
+    });
+
+    it("emits validate_required() for base-R4 required fields the profile inherits", () => {
+        const file = profileFile();
+        expect(file).toBeDefined();
+        expect(file).toContain('validate_required(self._resource, profile_name, "target")');
+        expect(file).toContain('validate_required(self._resource, profile_name, "recorded")');
+    });
+});