feat(langchain): refine reactAgent

.changeset/three-cats-sin.md

@@ -0,0 +1,12 @@
+---
+langchain: patch
+"@langchain/mcp-adapters": patch
+---
+
+Further refinements and improvements to createAgent with middleware:
+
+- updated createAgent symbol documentation
+- improved type handling for invoke and stream invocation parameter
+- acknowledge middleware context schema's that are optional or have default values as actually optional
+- improvements to HITL middleware: support for multiple tool interrupts at the same time
+- updates `@langchain/mcp-adapters` examples to use the new createAgent primitive from langchain

examples/package.json

@@ -52,7 +52,7 @@
     "@langchain/google-vertexai": "workspace:*",
     "@langchain/google-vertexai-web": "workspace:*",
     "@langchain/groq": "workspace:*",
-    "@langchain/langgraph": "alpha",
+    "@langchain/langgraph": "next",
     "@langchain/mistralai": "workspace:*",
     "@langchain/mongodb": "workspace:*",
     "@langchain/nomic": "workspace:*",

examples/src/createAgent/middleware/hitl.ts

@@ -54,12 +54,10 @@ const writeFileTool = tool(
 const hitlMiddleware = humanInTheLoopMiddleware({
   toolConfigs: {
     write_file: {
-      requireApproval: true,
+      allowAccept: true,
       description: "⚠️ File write operation requires approval",
     },
-    calculator: {
-      requireApproval: false, // Math is safe
-    },
+    calculator: false, // Math is safe
   },
 });
 

internal/eslint/package.json

@@ -4,8 +4,8 @@
   "description": "Shared ESLint configuration for LangChain.js projects",
   "author": "LangChain",
   "license": "MIT",
-  "main": "./index.ts",
-  "types": "./index.ts",
+  "main": "./src/index.ts",
+  "types": "./src/index.ts",
   "type": "module",
   "keywords": [
     "eslint",

libs/langchain-community/src/load/import_map.ts

@@ -82,7 +82,37 @@ export * as llms__togetherai from "../llms/togetherai.js";
 export * as llms__watsonx_ai from "../llms/watsonx_ai.js";
 export * as llms__writer from "../llms/writer.js";
 export * as llms__yandex from "../llms/yandex.js";
+export * as llms__layerup_security from "../llms/layerup_security.js";
+export * as vectorstores__analyticdb from "../vectorstores/analyticdb.js";
+export * as vectorstores__astradb from "../vectorstores/astradb.js";
+export * as vectorstores__azion_edgesql from "../vectorstores/azion_edgesql.js";
+export * as vectorstores__azure_aisearch from "../vectorstores/azure_aisearch.js";
+export * as vectorstores__azure_cosmosdb from "../vectorstores/azure_cosmosdb.js";
+export * as vectorstores__cassandra from "../vectorstores/cassandra.js";
+export * as vectorstores__chroma from "../vectorstores/chroma.js";
+export * as vectorstores__clickhouse from "../vectorstores/clickhouse.js";
+export * as vectorstores__closevector__node from "../vectorstores/closevector/node.js";
+export * as vectorstores__closevector__web from "../vectorstores/closevector/web.js";
+export * as vectorstores__cloudflare_vectorize from "../vectorstores/cloudflare_vectorize.js";
+export * as vectorstores__convex from "../vectorstores/convex.js";
 export * as vectorstores__couchbase_search from "../vectorstores/couchbase_search.js";
+export * as vectorstores__elasticsearch from "../vectorstores/elasticsearch.js";
+export * as vectorstores__faiss from "../vectorstores/faiss.js";
+export * as vectorstores__googlevertexai from "../vectorstores/googlevertexai.js";
+export * as vectorstores__hnswlib from "../vectorstores/hnswlib.js";
+export * as vectorstores__hanavector from "../vectorstores/hanavector.js";
+export * as vectorstores__lancedb from "../vectorstores/lancedb.js";
+export * as vectorstores__libsql from "../vectorstores/libsql.js";
+export * as vectorstores__mariadb from "../vectorstores/mariadb.js";
+export * as vectorstores__milvus from "../vectorstores/milvus.js";
+export * as vectorstores__momento_vector_index from "../vectorstores/momento_vector_index.js";
+export * as vectorstores__mongodb_atlas from "../vectorstores/mongodb_atlas.js";
+export * as vectorstores__myscale from "../vectorstores/myscale.js";
+export * as vectorstores__neo4j_vector from "../vectorstores/neo4j_vector.js";
+export * as vectorstores__neon from "../vectorstores/neon.js";
+export * as vectorstores__opensearch from "../vectorstores/opensearch.js";
+export * as vectorstores__pgvector from "../vectorstores/pgvector.js";
+export * as vectorstores__pinecone from "../vectorstores/pinecone.js";
 export * as vectorstores__prisma from "../vectorstores/prisma.js";
 export * as vectorstores__qdrant from "../vectorstores/qdrant.js";
 export * as vectorstores__redis from "../vectorstores/redis.js";

libs/langchain-core/src/messages/index.ts

@@ -9,16 +9,7 @@ export * from "./transformers.js";
 export * from "./metadata.js";
 export * from "./message.js";
 export * from "./modifier.js";
-// TODO: Use a star export when we deprecate the
-// existing "ToolCall" type in "base.js".
-export {
-  type ToolMessageFields,
-  ToolMessage,
-  ToolMessageChunk,
-  type InvalidToolCall,
-  isToolMessage,
-  isToolMessageChunk,
-} from "./tool.js";
+export * from "./tool.js";
 
 // This is an old export for backwards compatibility with existing multimodal content blocks
 // TODO: remove this in v2

libs/langchain/package.json

@@ -79,7 +79,7 @@
   },
   "dependencies": {
     "@langchain/textsplitters": "workspace:*",
-    "@langchain/langgraph": "^1.0.0-alpha",
+    "@langchain/langgraph": "next",
     "@langchain/langgraph-checkpoint": "^0.1.1",
     "js-yaml": "^4.1.0",
     "jsonpointer": "^5.0.1",

libs/langchain/src/agents/interrupt.ts

@@ -1,5 +1,19 @@
 export { interrupt } from "@langchain/langgraph";
 
+/**
+ * Represents information about an interrupt.
+ */
+export interface Interrupt<TValue = unknown> {
+  /**
+   * The ID of the interrupt.
+   */
+  id: string;
+  /**
+   * The requests for human input.
+   */
+  value: TValue;
+}
+
 /**
  * Configuration interface that defines what actions are allowed for a human interrupt.
  * This controls the available interaction options when the graph is paused for human input.