diff --git a/src/java_codebase_rag/absence/absence_vocab.py b/src/java_codebase_rag/absence/absence_vocab.py
index 6d041e0..a6deb39 100644
--- a/src/java_codebase_rag/absence/absence_vocab.py
+++ b/src/java_codebase_rag/absence/absence_vocab.py
@@ -375,8 +375,13 @@ def get_vocabulary_index(graph: Any, cfg: Any) -> VocabularyIndex:
         # (JSONDecodeError/KeyError) — all subsumed by Exception; rebuild.
         log.debug(f"Vocab index missing/stale/corrupt ({e}), rebuilding from graph")
 
-        # Build from graph
-        index = VocabularyIndex.build(graph, q=cfg.absence_ngram_q)
+        # Build from graph. Coerce q to int (mirror absence_diagnosis.py's
+        # int(getattr(cfg, ...)) pattern): a non-int cfg.absence_ngram_q (e.g. a
+        # MagicMock cfg from a leaked test mock, or a YAML string) would otherwise
+        # crash _qgrams at `len(text) < q` ('int < MagicMock'). Default 3 = the
+        # config default for absence_ngram_q.
+        q = int(getattr(cfg, "absence_ngram_q", 3) or 3)
+        index = VocabularyIndex.build(graph, q=q)
 
         # Save to sidecar (best-effort)
         try:
diff --git a/src/java_codebase_rag/jrag_envelope.py b/src/java_codebase_rag/jrag_envelope.py
index cc7249c..cfdd50d 100644
--- a/src/java_codebase_rag/jrag_envelope.py
+++ b/src/java_codebase_rag/jrag_envelope.py
@@ -16,6 +16,7 @@
 import json
 import re
 from dataclasses import dataclass, field
+from pathlib import Path
 from typing import Any, Literal
 
 from java_codebase_rag.absence.absence_types import AbsenceDiagnosis
@@ -274,10 +275,22 @@ def simple_name(node_dict: dict[str, Any]) -> str:
 
     ``NodeRef`` carries no ``name`` field; the rendering layer derives a short
     label from the FQN on demand. Empty/missing FQN returns "".
+
+    File/package Symbol nodes are the exception: their ``fqn`` is a filesystem
+    path (e.g. ``chat-assign/.../AssignConfiguration.java``), so the dot-split
+    would yield the file *extension* (``java``) instead of a name. When the fqn
+    is a path (contains ``/`` — the indexer POSIX-normalizes via ``.as_posix()``
+    so backslashes don't occur) we return the basename. Route fqns
+    (``"GET /api/x"``) also contain ``/`` but carry a space, so they're excluded
+    here and stay on the dot-split path.
     """
     fqn = str(node_dict.get("fqn") or "")
     if not fqn:
         return ""
+    if "/" in fqn and " " not in fqn:
+        base = Path(fqn).name
+        if base:
+            return base
     return fqn.rsplit(".", 1)[-1]
 
 
diff --git a/src/java_codebase_rag/mcp/mcp_v2.py b/src/java_codebase_rag/mcp/mcp_v2.py
index 3cccedf..f2e1544 100644
--- a/src/java_codebase_rag/mcp/mcp_v2.py
+++ b/src/java_codebase_rag/mcp/mcp_v2.py
@@ -1120,6 +1120,20 @@ def find_v2(
         fetch_cap = int(limit) + int(offset) + 1
         if kind == "symbol":
             where, params = _symbol_where_from_filter(nf)
+            # Exclude structural Symbol nodes. Files and packages are :Symbol-
+            # labeled (kind='file'/'package') but aren't code declarations —
+            # without this, `fqn_contains` matches their filesystem-path fqn
+            # (e.g. 'Assign' in '.../DevAssignmentController.java') and surfaces
+            # them as hits. Mirrors search_lexical.py. Safe to apply
+            # unconditionally: DeclarationSymbolKind (the only values
+            # symbol_kind/symbol_kinds can take) excludes 'file'/'package', so no
+            # filter ever requests them.
+            struct_pred = "(s.kind <> 'file' AND s.kind <> 'package')"
+            where = (
+                f"WHERE {struct_pred}"
+                if not where
+                else where.replace("WHERE ", f"WHERE {struct_pred} AND ", 1)
+            )
             params["lim"] = fetch_cap
             rows = g._rows(  # noqa: SLF001
                 f"MATCH (s:Symbol) {where} RETURN s.id AS id, s.fqn AS fqn, s.microservice AS microservice, "
diff --git a/tests/absence/test_absence_mcp_integration.py b/tests/absence/test_absence_mcp_integration.py
index a357829..5a3ef18 100644
--- a/tests/absence/test_absence_mcp_integration.py
+++ b/tests/absence/test_absence_mcp_integration.py
@@ -216,3 +216,40 @@ def test_resolve_non_empty_result_has_no_absence(ladybug_graph) -> None:
     assert out.success is True
     assert out.status in ("one", "many")
     assert out.absence is None
+
+
+# --- Absence-config singleton isolation regression ---
+#
+# server.main() caches the operator cfg in a module-global singleton via
+# set_absence_config() (mcp/server.py). Tests that drive server.main() with a
+# MOCKED resolve_operator_config (tests/package/test_java_codebase_rag_cli.py)
+# cache a MagicMock there, and monkeypatch does NOT revert it (set via a function
+# call, not an attribute patch). On the graph-only macOS Intel CI leg this leaks
+# into later absence/resolve tests in the same xdist worker and surfaces as
+# `int < MagicMock` (best_sim < cfg.absence_absent_floor). The autouse
+# `_reset_absence_config_singleton` fixture in conftest.py is the fix; the pair
+# below pins the cross-test isolation contract. Runs in definition order.
+
+
+def test_absence_config_singleton_leak_regression_poison() -> None:
+    """Part 1: simulate server.main() caching a MagicMock cfg in the singleton."""
+    from unittest.mock import MagicMock
+
+    from java_codebase_rag.analysis import resolve_service
+    from java_codebase_rag.mcp import mcp_v2
+
+    mcp_v2._absence_config = MagicMock()
+    resolve_service._absence_config = MagicMock()
+    assert isinstance(mcp_v2._absence_config, MagicMock)
+
+
+def test_absence_config_singleton_leak_regression_is_clean() -> None:
+    """Part 2: the autouse isolation fixture must have reset the poisoned singleton
+    from part 1, so absence/resolve tools build a real config (no `int < MagicMock`).
+    Fails if the `_reset_absence_config_singleton` fixture is removed/broken.
+    """
+    from java_codebase_rag.analysis import resolve_service
+    from java_codebase_rag.mcp import mcp_v2
+
+    assert mcp_v2._absence_config is None
+    assert resolve_service._absence_config is None
diff --git a/tests/conftest.py b/tests/conftest.py
index 240858a..0a1959e 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -97,6 +97,33 @@ def _enforce_dev_deps() -> None:
         )
 
 
+@pytest.fixture(autouse=True)
+def _reset_absence_config_singleton():
+    """Isolate the module-global absence-diagnosis config between tests.
+
+    ``server.main()`` calls ``mcp_v2.set_absence_config(cfg)`` and
+    ``resolve_service.set_absence_config(cfg)`` (mcp/server.py), caching ``cfg`` in
+    a module-global singleton. Tests that drive ``server.main()`` with a *mocked*
+    ``resolve_operator_config`` (tests/package/test_java_codebase_rag_cli.py) cache
+    a ``MagicMock`` there. ``monkeypatch`` does NOT revert it — the value is set via
+    a function call, not an attribute patch — so it leaks across tests in the same
+    xdist worker (``--dist loadfile``). Later absence/resolve tests then read the
+    mock; ``get_vocabulary_index`` passes ``cfg.absence_ngram_q`` (a MagicMock)
+    uncoerced into ``_qgrams`` → ``len(text) < q`` → ``int < MagicMock``
+    (absence_vocab.py), surfacing as flaky ``success=False`` failures on the
+    graph-only macOS Intel CI leg. Resetting here guarantees each test sees a clean
+    config. (The production side also coerces ``q`` to int as defense-in-depth.)
+    """
+    from java_codebase_rag.analysis import resolve_service
+    from java_codebase_rag.mcp import mcp_v2
+
+    mcp_v2._absence_config = None
+    resolve_service._absence_config = None
+    yield
+    mcp_v2._absence_config = None
+    resolve_service._absence_config = None
+
+
 @pytest.fixture(scope="session")
 def corpus_root() -> Path:
     assert CORPUS_ROOT.is_dir(), f"corpus missing: {CORPUS_ROOT}"
diff --git a/tests/mcp/test_mcp_v2.py b/tests/mcp/test_mcp_v2.py
index a6f614a..fe99412 100644
--- a/tests/mcp/test_mcp_v2.py
+++ b/tests/mcp/test_mcp_v2.py
@@ -171,8 +171,32 @@ def test_find_symbol_empty_filter_returns_results(ladybug_graph) -> None:
     out = find_v2("symbol", {}, graph=ladybug_graph)
     assert out.success is True
     assert out.results
-    # Regression guard: Symbol rows can include non-declaration kinds (e.g., package/file).
+    # Every returned row is a code declaration with a non-empty kind ...
     assert all(isinstance(r.symbol_kind, str) and r.symbol_kind for r in out.results)
+    # ... and structural file/package Symbol nodes are excluded (they are not
+    # code declarations). See test_find_symbol_excludes_file_and_package_nodes.
+    kinds = {r.symbol_kind for r in out.results}
+    assert "file" not in kinds
+    assert "package" not in kinds
+
+
+def test_find_symbol_excludes_file_and_package_nodes(ladybug_graph) -> None:
+    """File/package Symbol nodes are structural, not code declarations, so find_v2
+    must never surface them. Their ``fqn`` is a filesystem path, so a substring
+    filter otherwise matches the *filename* (e.g. ``Assign`` in
+    ``.../DevAssignmentController.java``) and leaks a file row whose rendered
+    label collapses to the ``java`` extension. Reproduces the chat-assign case.
+    """
+    out = find_v2("symbol", {"fqn_contains": "Assign"}, graph=ladybug_graph)
+    assert out.success is True
+    assert out.results, "fixture (bank-chat-system) has Assign-named declarations"
+    kinds = {r.symbol_kind for r in out.results}
+    assert "file" not in kinds
+    # 'package' can't match here (CONTAINS is case-sensitive and package fqns are
+    # lowercase) — the package exclusion is proven by test_find_symbol_empty_filter_returns_results.
+    assert "package" not in kinds
+    # Real declarations still surface (the chat-assign module has Assign* types).
+    assert kinds & {"class", "interface", "enum", "record", "annotation", "method", "constructor"}
 
 
 def test_find_symbol_by_symbol_kind_method(ladybug_graph) -> None:
diff --git a/tests/package/test_jrag_render.py b/tests/package/test_jrag_render.py
index ea9e706..67454ce 100644
--- a/tests/package/test_jrag_render.py
+++ b/tests/package/test_jrag_render.py
@@ -396,6 +396,39 @@ def test_simple_name_derived_from_fqn() -> None:
     assert simple_name({}) == ""
 
 
+def test_simple_name_file_path_fqn_returns_basename_not_extension() -> None:
+    """File/package Symbol nodes carry a filesystem path as ``fqn``; the dot-split
+    would otherwise yield the file *extension* (``java``) instead of a name.
+    A path-shaped fqn returns its basename; a route fqn (``"GET /api/x"``) still
+    has a space so it stays on the dot-split path; a package fqn (dots only) is
+    unchanged.
+    """
+    assert simple_name({"fqn": "chat-assign/src/main/java/com/bank/chat/assign/config/AssignConfiguration.java"}) == "AssignConfiguration.java"
+    assert simple_name({"fqn": "src/main/java/Foo.java"}) == "Foo.java"
+    # Package node fqn: dots only, no separator -> unchanged dot-split.
+    assert simple_name({"fqn": "com.bank.chat.assign"}) == "assign"
+    # Route fqn contains '/' but also a space -> NOT treated as a path.
+    assert simple_name({"fqn": "GET /api/assign"}) == "GET /api/assign"
+
+
+def test_render_listing_file_node_shows_basename_not_extension() -> None:
+    """User-visible symptom guard: a file Symbol node (fqn = filesystem path) must
+    render its basename, never collapse to the ``java`` extension. Covers the
+    render path (display_name -> simple_name) end-to-end, complementing the
+    simple_name unit test. Defense-in-depth for Layer 2: Layer 1 keeps file nodes
+    out of `find`, but query-mode exact match or traversal can still surface one.
+    """
+    from java_codebase_rag.jrag_render import display_name
+
+    node = {"fqn": "chat-assign/src/main/java/com/bank/chat/assign/config/AssignConfiguration.java"}
+    # The label is the basename, not the 'java' extension.
+    assert display_name(node) == "AssignConfiguration.java"
+    # And it reaches the rendered listing the user actually sees.
+    env = Envelope(status="ok", nodes={"sym:1": node})
+    out = render(env, fmt="text", noun="matches")
+    assert "AssignConfiguration.java" in out
+
+
 # ----- Bonus: tiered_name tiers -----