feat: migrate to langchain v1

package.json

@@ -59,7 +59,8 @@
   "xo": [
     {
       "ignores": [
-        "**/*.genai.mjs"
+        "**/*.genai.mjs",
+        "**/vite.config.ts"
       ]
     },
     {
@@ -90,6 +91,7 @@
         "import/extensions": "off",
         "n/prefer-global/process": "off",
         "no-new-func": "off",
+        "capitalized-comments": "off",
         "unicorn/no-process-exit": "off",
         "unicorn/prefer-add-event-listener": "off",
         "unicorn/prefer-switch": "off",

packages/agent-api/package.json

@@ -22,17 +22,17 @@
     "@azure/identity": "^4.2.0",
     "@azure/monitor-opentelemetry": "^1.12.0",
     "@azure/storage-blob": "^12.17.0",
-    "@langchain/azure-cosmosdb": "^0.2.9",
-    "@langchain/core": "^0.3.18",
-    "@langchain/langgraph": "^0.4.9",
-    "@langchain/mcp-adapters": "^0.6.0",
-    "@langchain/openai": "^0.6.13",
+    "@langchain/azure-cosmosdb": "^1.0.0",
+    "@langchain/core": "^1.0.0",
+    "@langchain/langgraph": "^1.0.0",
+    "@langchain/mcp-adapters": "^1.0.0",
+    "@langchain/openai": "^1.0.0",
     "@modelcontextprotocol/sdk": "^1.20.0",
     "@opentelemetry/exporter-trace-otlp-http": "^0.206.0",
     "@opentelemetry/instrumentation": "^0.206.0",
     "@opentelemetry/sdk-trace-base": "^2.1.0",
     "@opentelemetry/sdk-trace-node": "^2.0.1",
-    "langchain": "^0.3.34"
+    "langchain": "^1.0.0"
   },
   "devDependencies": {
     "@types/node": "^22",

packages/agent-api/src/functions/chats-post.ts

@@ -1,12 +1,11 @@
 import { Readable } from 'node:stream';
 import { randomUUID } from 'node:crypto';
 import { HttpRequest, InvocationContext, HttpResponseInit, app } from '@azure/functions';
+import { createAgent, AIMessage, HumanMessage } from 'langchain';
 import { ChatOpenAI } from '@langchain/openai';
 import { AzureCosmsosDBNoSQLChatMessageHistory } from '@langchain/azure-cosmosdb';
-import { createReactAgent } from '@langchain/langgraph/prebuilt';
-import { AIMessage, HumanMessage } from '@langchain/core/messages';
 import { loadMcpTools } from '@langchain/mcp-adapters';
-import { StreamEvent } from '@langchain/core/tracers/log_stream.js';
+import { StreamEvent } from '@langchain/core/dist/tracers/log_stream.js';
 import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/streamableHttp.js';
 import { Client } from '@modelcontextprotocol/sdk/client/index.js';
 import { getAzureOpenAiTokenProvider, getCredentials, getInternalUserId } from '../auth.js';
@@ -117,10 +116,10 @@ export async function postChats(request: HttpRequest, context: InvocationContext
     const tools = await loadMcpTools('burger', client);
     context.log(`Loaded ${tools.length} tools from Burger MCP server`);
 
-    const agent = createReactAgent({
-      llm: model,
+    const agent = createAgent({
+      model,
       tools,
-      prompt: agentSystemPrompt,
+      systemPrompt: agentSystemPrompt,
     });
 
     const question = messages.at(-1)!.content;
@@ -160,7 +159,8 @@ export async function postChats(request: HttpRequest, context: InvocationContext
       try {
         if (content) {
           // When no content is generated, do not update the history as it's likely an error
-          await chatHistory.addMessages([new HumanMessage(question), new AIMessage(content)]);
+          await chatHistory.addMessage(new HumanMessage(question));
+          await chatHistory.addMessage(new AIMessage(content));
           context.log('Chat history updated successfully');
 
           // Ensure the session title has finished generating

packages/agent-api/src/tracing.ts

@@ -6,8 +6,8 @@ import { useAzureMonitor } from '@azure/monitor-opentelemetry';
 import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-http';
 import { NodeTracerProvider } from '@opentelemetry/sdk-trace-node';
 import { SimpleSpanProcessor } from '@opentelemetry/sdk-trace-base';
-import { LangChainInstrumentation } from '@arizeai/openinference-instrumentation-langchain';
-import * as CallbackManagerModule from '@langchain/core/callbacks/manager';
+// import { LangChainInstrumentation } from '@arizeai/openinference-instrumentation-langchain';
+// import * as CallbackManagerModule from 'langchain';
 
 let isTracingInitialized = false;
 if (!isTracingInitialized) {
@@ -35,8 +35,9 @@ if (!isTracingInitialized) {
   }
 
   // Manually instrument LangChain's CallbackManager to capture traces
-  const langchainInstrumentation = new LangChainInstrumentation();
-  langchainInstrumentation.manuallyInstrument(CallbackManagerModule);
+  // TODO: temporarily disabled due to compatibility issues with LangChain v1 (PR in progress)
+  // const langchainInstrumentation = new LangChainInstrumentation();
+  // langchainInstrumentation.manuallyInstrument(CallbackManagerModule);
 
   isTracingInitialized = true;
 }

packages/agent-cli/agent-cli.ts

@@ -2,12 +2,11 @@ import path from 'node:path';
 import fs from 'node:fs/promises';
 import os from 'node:os';
 import { DefaultAzureCredential, getBearerTokenProvider } from '@azure/identity';
+import { createAgent, BaseMessage, HumanMessage, AIMessage } from 'langchain';
 import { ChatOpenAI } from '@langchain/openai';
-import { createReactAgent } from '@langchain/langgraph/prebuilt';
 import { loadMcpTools } from '@langchain/mcp-adapters';
 import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/streamableHttp.js';
 import { Client } from '@modelcontextprotocol/sdk/client/index.js';
-import { BaseMessage, HumanMessage, AIMessage } from '@langchain/core/messages';
 import dotenv from 'dotenv';
 
 dotenv.config({ path: path.join(process.cwd(), '../../.env'), quiet: true });
@@ -179,10 +178,10 @@ export async function run() {
     const tools = await loadMcpTools('burger', client);
     console.log(`Loaded ${tools.length} tools from Burger MCP server`);
 
-    const agent = createReactAgent({
-      llm: model,
+    const agent = createAgent({
+      model,
       tools,
-      prompt: agentSystemPrompt + (session.userId ? `\n\nUser ID: ${session.userId}` : ''),
+      systemPrompt: agentSystemPrompt + (session.userId ? `\n\nUser ID: ${session.userId}` : ''),
     });
 
     const chatHistory = convertHistoryToMessages(session.history);

packages/agent-cli/package.json

@@ -18,13 +18,13 @@
   "license": "MIT",
   "dependencies": {
     "@azure/identity": "^4.2.0",
-    "@langchain/core": "^0.3.18",
-    "@langchain/langgraph": "^0.4.9",
-    "@langchain/mcp-adapters": "^0.6.0",
-    "@langchain/openai": "^0.6.9",
+    "@langchain/core": "^1.0.0",
+    "@langchain/langgraph": "^1.0.0",
+    "@langchain/mcp-adapters": "^1.0.0",
+    "@langchain/openai": "^1.0.0",
     "@modelcontextprotocol/sdk": "^1.20.0",
     "dotenv": "^17.0.1",
-    "langchain": "^0.3.6"
+    "langchain": "^1.0.0"
   },
   "devDependencies": {
     "@types/node": "^22",