diff --git a/libs/langgraph-api/package.json b/libs/langgraph-api/package.json
index 2aa5af3..883bc92 100644
--- a/libs/langgraph-api/package.json
+++ b/libs/langgraph-api/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@langchain/langgraph-api",
-  "version": "0.0.39",
+  "version": "0.0.40",
   "type": "module",
   "engines": {
     "node": "^18.19.0 || >=20.16.0"
@@ -56,7 +56,7 @@
     "dotenv": "^16.4.7",
     "exit-hook": "^4.0.0",
     "hono": "^4.5.4",
-    "langsmith": "^0.2.15",
+    "langsmith": "^0.3.33",
     "open": "^10.1.0",
     "semver": "^7.7.1",
     "stacktrace-parser": "^0.1.10",
@@ -68,7 +68,7 @@
     "zod": "^3.23.8"
   },
   "peerDependencies": {
-    "@langchain/core": "^0.3.42",
+    "@langchain/core": "^0.3.59",
     "@langchain/langgraph": "^0.2.57 || ^0.3.0",
     "@langchain/langgraph-checkpoint": "~0.0.16",
     "@langchain/langgraph-sdk": "~0.0.70",
@@ -80,7 +80,7 @@
     }
   },
   "devDependencies": {
-    "@langchain/core": "^0.3.42",
+    "@langchain/core": "^0.3.59",
     "@langchain/langgraph": "^0.2.57",
     "@langchain/langgraph-checkpoint": "~0.0.16",
     "@langchain/langgraph-sdk": "^0.0.77",
diff --git a/libs/langgraph-api/src/api/meta.mts b/libs/langgraph-api/src/api/meta.mts
index 298e3c2..5e43144 100644
--- a/libs/langgraph-api/src/api/meta.mts
+++ b/libs/langgraph-api/src/api/meta.mts
@@ -1,7 +1,22 @@
 import { Hono } from "hono";
+import * as fs from "node:fs/promises";
+import * as url from "node:url";
 
 const api = new Hono();
 
+// Get the version using the same pattern as semver/index.mts
+const packageJsonPath = url.fileURLToPath(
+  new URL("../../package.json", import.meta.url),
+);
+
+let version: string;
+try {
+  const packageJson = JSON.parse(await fs.readFile(packageJsonPath, "utf-8"));
+  version = packageJson.version;
+} catch {
+  console.warn("Could not determine version of langgraph-api");
+}
+
 // read env variable
 const env = process.env;
 
@@ -24,7 +39,14 @@ api.get("/info", (c) => {
     return undefined;
   })();
   return c.json({
-    flags: { assistants: true, crons: false, langsmith: !!langsmithTracing },
+    version,
+    context: "js",
+    flags: {
+      assistants: true,
+      crons: false,
+      langsmith: !!langsmithTracing,
+      langsmith_tracing_replicas: true,
+    },
   });
 });
 
diff --git a/libs/langgraph-api/src/api/runs.mts b/libs/langgraph-api/src/api/runs.mts
index 3bcc83f..fbe17e0 100644
--- a/libs/langgraph-api/src/api/runs.mts
+++ b/libs/langgraph-api/src/api/runs.mts
@@ -1,20 +1,20 @@
+import { zValidator } from "@hono/zod-validator";
 import { Hono } from "hono";
 import { HTTPException } from "hono/http-exception";
 import { streamSSE } from "hono/streaming";
+import { v4 as uuid4 } from "uuid";
+import { z } from "zod";
+import type { AuthContext } from "../auth/index.mjs";
 import { getAssistantId } from "../graph/load.mjs";
-import { zValidator } from "@hono/zod-validator";
+import { logError, logger } from "../logging.mjs";
 import * as schemas from "../schemas.mjs";
-import { z } from "zod";
 import { type Run, type RunKwargs, Runs, Threads } from "../storage/ops.mjs";
-import { serialiseAsDict } from "../utils/serde.mjs";
 import {
   getDisconnectAbortSignal,
   jsonExtra,
   waitKeepAlive,
 } from "../utils/hono.mjs";
-import { logError, logger } from "../logging.mjs";
-import { v4 as uuid4 } from "uuid";
-import type { AuthContext } from "../auth/index.mjs";
+import { serialiseAsDict } from "../utils/serde.mjs";
 
 const api = new Hono();
 
@@ -52,6 +52,14 @@ const createValidRun = async (
     Object.assign(config.configurable, run.checkpoint);
   }
 
+  if (run.langsmith_tracer) {
+    config.configurable ??= {};
+    Object.assign(config.configurable, {
+      langsmith_project: run.langsmith_tracer.project_name,
+      langsmith_example_id: run.langsmith_tracer.example_id,
+    });
+  }
+
   if (headers) {
     for (const [rawKey, value] of headers.entries()) {
       const key = rawKey.toLowerCase();
diff --git a/libs/langgraph-api/src/schemas.mts b/libs/langgraph-api/src/schemas.mts
index c964d43..1880b62 100644
--- a/libs/langgraph-api/src/schemas.mts
+++ b/libs/langgraph-api/src/schemas.mts
@@ -175,6 +175,11 @@ export const CommandSchema = z.object({
   resume: z.unknown().optional(),
 });
 
+export const LangsmithTracer = z.object({
+  project_name: z.string().optional(),
+  example_id: z.string().optional(),
+});
+
 export const RunCreate = z
   .object({
     assistant_id: z.union([z.string().uuid(), z.string()]),
@@ -228,6 +233,7 @@ export const RunCreate = z
     if_not_exists: z.enum(["reject", "create"]).optional(),
     on_completion: z.enum(["delete", "keep"]).optional(),
     feedback_keys: z.array(z.string()).optional(),
+    langsmith_tracer: LangsmithTracer.optional(),
   })
   .describe("Payload for creating a stateful run.");
 
diff --git a/libs/langgraph-api/src/stream.mts b/libs/langgraph-api/src/stream.mts
index 34dc97b..a7cf1a9 100644
--- a/libs/langgraph-api/src/stream.mts
+++ b/libs/langgraph-api/src/stream.mts
@@ -1,19 +1,20 @@
-import type { Run, RunnableConfig, Checkpoint } from "./storage/ops.mjs";
-import { getGraph } from "./graph/load.mjs";
-import { Client as LangSmithClient } from "langsmith";
+import { BaseMessageChunk, isBaseMessage } from "@langchain/core/messages";
+import { LangChainTracer } from "@langchain/core/tracers/tracer_langchain";
 import {
   type CheckpointMetadata,
   type Interrupt,
   type StateSnapshot,
 } from "@langchain/langgraph";
 import type { Pregel } from "@langchain/langgraph/pregel";
+import { Client as LangSmithClient, getDefaultProjectName } from "langsmith";
+import { getLangGraphCommand } from "./command.mjs";
+import { getGraph } from "./graph/load.mjs";
+import { checkLangGraphSemver } from "./semver/index.mjs";
+import type { Checkpoint, Run, RunnableConfig } from "./storage/ops.mjs";
 import {
   runnableConfigToCheckpoint,
   taskRunnableConfigToCheckpoint,
 } from "./utils/runnableConfig.mjs";
-import { BaseMessageChunk, isBaseMessage } from "@langchain/core/messages";
-import { getLangGraphCommand } from "./command.mjs";
-import { checkLangGraphSemver } from "./semver/index.mjs";
 
 type LangGraphStreamMode = Pregel<any, any>["streamMode"][number];
 
@@ -197,6 +198,21 @@ export async function* streamState(
     langgraph_api_url: process.env.LANGGRAPH_API_URL ?? undefined,
   };
 
+  const tracer = run.kwargs?.config?.configurable?.langsmith_project
+    ? new LangChainTracer({
+        replicas: [
+          [
+            run.kwargs?.config?.configurable?.langsmith_project as string,
+            {
+              reference_example_id:
+                run.kwargs?.config?.configurable?.langsmith_example_id,
+            },
+          ],
+          [getDefaultProjectName(), undefined],
+        ],
+      })
+    : undefined;
+
   const events = graph.streamEvents(
     kwargs.command != null
       ? getLangGraphCommand(kwargs.command)
@@ -216,6 +232,7 @@ export async function* streamState(
       runId: run.run_id,
       streamMode: [...libStreamMode],
       signal: options?.signal,
+      ...(tracer && { callbacks: [tracer] }),
     },
   );
 
diff --git a/libs/langgraph-cli/package.json b/libs/langgraph-cli/package.json
index b4db907..7992a11 100644
--- a/libs/langgraph-cli/package.json
+++ b/libs/langgraph-cli/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@langchain/langgraph-cli",
-  "version": "0.0.39",
+  "version": "0.0.40",
   "type": "module",
   "engines": {
     "node": "^18.19.0 || >=20.16.0"
diff --git a/libs/langgraph-ui/package.json b/libs/langgraph-ui/package.json
index 6dce253..51b07d5 100644
--- a/libs/langgraph-ui/package.json
+++ b/libs/langgraph-ui/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@langchain/langgraph-ui",
-  "version": "0.0.39",
+  "version": "0.0.40",
   "type": "module",
   "engines": {
     "node": "^18.19.0 || >=20.16.0"
diff --git a/yarn.lock b/yarn.lock
index cca742a..604e3c9 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -382,23 +382,23 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@langchain/core@npm:^0.3.42":
-  version: 0.3.57
-  resolution: "@langchain/core@npm:0.3.57"
+"@langchain/core@npm:^0.3.59":
+  version: 0.3.59
+  resolution: "@langchain/core@npm:0.3.59"
   dependencies:
     "@cfworker/json-schema": ^4.0.2
     ansi-styles: ^5.0.0
     camelcase: 6
     decamelize: 1.2.0
     js-tiktoken: ^1.0.12
-    langsmith: ^0.3.29
+    langsmith: ^0.3.33
     mustache: ^4.2.0
     p-queue: ^6.6.2
     p-retry: 4
     uuid: ^10.0.0
-    zod: ^3.22.4
+    zod: ^3.25.32
     zod-to-json-schema: ^3.22.3
-  checksum: 5a497553209a3fe0c2a31b23c9586f586ea8b0785cb437a0b7140c308be80f0caa4397c45a4d7f0a1b7056f3509b03663f6c714217b75c20cce0a2df4fb3c105
+  checksum: 7ad68340baaa45dbdb94393345b23680fb57633aea3a3f766a96329b8521acd54197f68faa6ee8c12249d8bd5737f5cb37cc508df62dbfe4bf00b20af1cef8fa
   languageName: node
   linkType: hard
 
@@ -409,7 +409,7 @@ __metadata:
     "@babel/code-frame": ^7.26.2
     "@hono/node-server": ^1.12.0
     "@hono/zod-validator": ^0.2.2
-    "@langchain/core": ^0.3.42
+    "@langchain/core": ^0.3.59
     "@langchain/langgraph": ^0.2.57
     "@langchain/langgraph-checkpoint": ~0.0.16
     "@langchain/langgraph-sdk": ^0.0.77
@@ -427,7 +427,7 @@ __metadata:
     exit-hook: ^4.0.0
     hono: ^4.5.4
     jose: ^6.0.10
-    langsmith: ^0.2.15
+    langsmith: ^0.3.33
     open: ^10.1.0
     postgres: ^3.4.5
     prettier: ^3.3.3
@@ -442,7 +442,7 @@ __metadata:
     winston-console-format: ^1.0.8
     zod: ^3.23.8
   peerDependencies:
-    "@langchain/core": ^0.3.42
+    "@langchain/core": ^0.3.59
     "@langchain/langgraph": ^0.2.57 || ^0.3.0
     "@langchain/langgraph-checkpoint": ~0.0.16
     "@langchain/langgraph-sdk": ~0.0.70
@@ -2228,9 +2228,9 @@ __metadata:
   languageName: node
   linkType: hard
 
-"langsmith@npm:^0.3.29":
-  version: 0.3.29
-  resolution: "langsmith@npm:0.3.29"
+"langsmith@npm:^0.3.33":
+  version: 0.3.33
+  resolution: "langsmith@npm:0.3.33"
   dependencies:
     "@types/uuid": ^10.0.0
     chalk: ^4.1.2
@@ -2244,7 +2244,7 @@ __metadata:
   peerDependenciesMeta:
     openai:
       optional: true
-  checksum: 5e714752d40bd90525436d2d977ed0e750031f946dbc6c5549a1d7ceb5546b48dfcc23a1fb1b758f18d954fe53e6089b7ca600c60f2f72d854aa24d5ff0a41fa
+  checksum: 45970dbc711d3c84b1603d26291b9164ca6daf6d802f151af6c3ccdbfb84068be390366dbb15319a158ccf50e7e9f161c55abe84bce2730f93962888b33e6269
   languageName: node
   linkType: hard
 
@@ -3807,9 +3807,9 @@ __metadata:
   languageName: node
   linkType: hard
 
-"zod@npm:^3.22.4, zod@npm:^3.23.8":
-  version: 3.25.20
-  resolution: "zod@npm:3.25.20"
-  checksum: fce59e8727a1403b52158ea3b92f3cec23556dc014174ccabe49910fb4d59f0031df3a687a5941885dd26dc5d263ef976c5c07099e07b68c208f0049ef9f05a5
+"zod@npm:^3.23.8, zod@npm:^3.25.32":
+  version: 3.25.67
+  resolution: "zod@npm:3.25.67"
+  checksum: 56ab904d33b1cd00041ce64ae05b0628fcbfeb7e707fa31cd498a97b540135e4dfe685200c9c62aea307695ee132870b4bc34f035228ea728aa75cc96a4954cb
   languageName: node
   linkType: hard