fix(core): Instrument langgraph createReactAgent

dev-packages/node-integration-tests/suites/tracing/langgraph/agent-scenario.mjs

@@ -0,0 +1,70 @@
+import { ChatAnthropic } from '@langchain/anthropic';
+import { HumanMessage, SystemMessage } from '@langchain/core/messages';
+import { createReactAgent } from '@langchain/langgraph/prebuilt';
+import * as Sentry from '@sentry/node';
+import express from 'express';
+
+function startMockAnthropicServer() {
+  const app = express();
+  app.use(express.json());
+
+  app.post('/v1/messages', (req, res) => {
+    const model = req.body.model;
+
+    // Simulate basic response
+    res.json({
+      id: 'msg_react_agent_123',
+      type: 'message',
+      role: 'assistant',
+      content: [
+        {
+          type: 'text',
+          text: 'Mock response from Anthropic!',
+        },
+      ],
+      model: model,
+      stop_reason: 'end_turn',
+      stop_sequence: null,
+      usage: {
+        input_tokens: 10,
+        output_tokens: 15,
+      },
+    });
+  });
+
+  return new Promise(resolve => {
+    const server = app.listen(0, () => {
+      resolve(server);
+    });
+  });
+}
+
+async function run() {
+  const server = await startMockAnthropicServer();
+  const baseUrl = `http://localhost:${server.address().port}`;
+
+  await Sentry.startSpan({ op: 'function', name: 'main' }, async () => {
+    // Create mocked LLM instance
+    const llm = new ChatAnthropic({
+      model: 'claude-3-5-sonnet-20241022',
+      apiKey: 'mock-api-key',
+      clientOptions: {
+        baseURL: baseUrl,
+      },
+    });
+
+    // Create a simple react agent with no tools
+    const agent = createReactAgent({ llm, tools: [] });
+
+    // Test: basic invocation
+    await agent.invoke({
+      messages: [new SystemMessage('You are a helpful assistant.'), new HumanMessage('What is the weather today?')],
+    });
+  });
+
+  await Sentry.flush(2000);
+
+  server.close();
+}
+
+run();

dev-packages/node-integration-tests/suites/tracing/langgraph/test.ts

@@ -205,4 +205,44 @@ describe('LangGraph integration', () => {
       await createRunner().ignore('event').expect({ transaction: EXPECTED_TRANSACTION_WITH_TOOLS }).start().completed();
     });
   });
+
+  const EXPECTED_TRANSACTION_REACT_AGENT = {
+    transaction: 'main',
+    spans: expect.arrayContaining([
+      // create_agent span
+      expect.objectContaining({
+        data: expect.objectContaining({
+          'gen_ai.operation.name': 'create_agent',
+          'sentry.op': 'gen_ai.create_agent',
+          'sentry.origin': 'auto.ai.langgraph',
+        }),
+        description: expect.stringContaining('create_agent'),
+        op: 'gen_ai.create_agent',
+        origin: 'auto.ai.langgraph',
+        status: 'ok',
+      }),
+      // invoke_agent span
+      expect.objectContaining({
+        data: expect.objectContaining({
+          'gen_ai.operation.name': 'invoke_agent',
+          'sentry.op': 'gen_ai.invoke_agent',
+          'sentry.origin': 'auto.ai.langgraph',
+        }),
+        description: expect.stringContaining('invoke_agent'),
+        op: 'gen_ai.invoke_agent',
+        origin: 'auto.ai.langgraph',
+        status: 'ok',
+      }),
+    ]),
+  };
+
+  createEsmAndCjsTests(__dirname, 'agent-scenario.mjs', 'instrument.mjs', (createRunner, test) => {
+    test('should instrument LangGraph createReactAgent with default PII settings', async () => {
+      await createRunner()
+        .ignore('event')
+        .expect({ transaction: EXPECTED_TRANSACTION_REACT_AGENT })
+        .start()
+        .completed();
+    });
+  });
 });

packages/core/src/index.ts

@@ -152,7 +152,7 @@ export type { GoogleGenAIResponse } from './tracing/google-genai/types';
 export { createLangChainCallbackHandler } from './tracing/langchain';
 export { LANGCHAIN_INTEGRATION_NAME } from './tracing/langchain/constants';
 export type { LangChainOptions, LangChainIntegration } from './tracing/langchain/types';
-export { instrumentStateGraphCompile, instrumentLangGraph } from './tracing/langgraph';
+export { instrumentStateGraphCompile, instrumentCreateReactAgent, instrumentLangGraph } from './tracing/langgraph';
 export { LANGGRAPH_INTEGRATION_NAME } from './tracing/langgraph/constants';
 export type { LangGraphOptions, LangGraphIntegration, CompiledGraph } from './tracing/langgraph/types';
 export type { OpenAiClient, OpenAiOptions, InstrumentedMethod } from './tracing/openai/types';

packages/core/src/tracing/langgraph/index.ts

@@ -156,6 +156,58 @@ function instrumentCompiledGraphInvoke(
   }) as (...args: unknown[]) => Promise<unknown>;
 }
 
+/**
+ * Instruments createReactAgent to create spans for agent creation and invocation
+ *
+ * Creates a `gen_ai.create_agent` span when createReactAgent() is called
+ */
+export function instrumentCreateReactAgent(
+  originalCreateReactAgent: (...args: unknown[]) => CompiledGraph,
+  options: LangGraphOptions,
+): (...args: unknown[]) => CompiledGraph {
+  return new Proxy(originalCreateReactAgent, {
+    apply(target, thisArg, args: unknown[]): CompiledGraph {
+      return startSpan(
+        {
+          op: 'gen_ai.create_agent',
+          name: 'create_agent',
+          attributes: {
+            [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: LANGGRAPH_ORIGIN,
+            [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'gen_ai.create_agent',
+            [GEN_AI_OPERATION_NAME_ATTRIBUTE]: 'create_agent',
+          },
+        },
+        span => {
+          try {
+            const compiledGraph = Reflect.apply(target, thisArg, args);
+            const compiledOptions = args.length > 0 ? (args[0] as Record<string, unknown>) : {};
+            const originalInvoke = compiledGraph.invoke;
+            if (originalInvoke && typeof originalInvoke === 'function') {
+              compiledGraph.invoke = instrumentCompiledGraphInvoke(
+                originalInvoke.bind(compiledGraph) as (...args: unknown[]) => Promise<unknown>,
+                compiledGraph,
+                compiledOptions,
+                options,
+              ) as typeof originalInvoke;
+            }
+
+            return compiledGraph;
+          } catch (error) {
+            span.setStatus({ code: SPAN_STATUS_ERROR, message: 'internal_error' });
+            captureException(error, {
+              mechanism: {
+                handled: false,
+                type: 'auto.ai.langgraph.error',
+              },
+            });
+            throw error;
+          }
+        },
+      );
+    },
+  }) as (...args: unknown[]) => CompiledGraph;
+}
+
 /**
  * Directly instruments a StateGraph instance to add tracing spans
  *

packages/node/src/integrations/tracing/langgraph/instrumentation.ts

@@ -6,7 +6,7 @@ import {
   InstrumentationNodeModuleFile,
 } from '@opentelemetry/instrumentation';
 import type { CompiledGraph, LangGraphOptions } from '@sentry/core';
-import { getClient, instrumentStateGraphCompile, SDK_VERSION } from '@sentry/core';
+import { getClient, instrumentCreateReactAgent, instrumentStateGraphCompile, SDK_VERSION } from '@sentry/core';
 
 const supportedVersions = ['>=0.0.0 <2.0.0'];
 
@@ -50,8 +50,31 @@ export class SentryLangGraphInstrumentation extends InstrumentationBase<LangGrap
           this._patch.bind(this),
           exports => exports,
         ),
+        new InstrumentationNodeModuleFile(
+          /**
+           * In CJS, LangGraph packages re-export from dist/prebuilt/index.cjs files.
+           * Patching only the root module sometimes misses the real implementation or
+           * gets overwritten when that file is loaded. We add a file-level patch so that
+           * _patch runs again on the concrete implementation
+           */
+          '@langchain/langgraph/dist/prebuilt/index.cjs',
+          supportedVersions,
+          this._patch.bind(this),
+          exports => exports,
+        ),
+        new InstrumentationNodeModuleFile(
+          /**
+           * ESM builds use dist/prebuilt/index.js (without .cjs extension)
+           * This catches ESM imports that resolve through the main package
+           */
+          '@langchain/langgraph/dist/prebuilt/index.js',
+          supportedVersions,
+          this._patch.bind(this),
+          exports => exports,
+        ),
       ],
     );
+
     return module;
   }
 
@@ -83,6 +106,17 @@ export class SentryLangGraphInstrumentation extends InstrumentationBase<LangGrap
       );
     }
 
+    // Patch createReactAgent to instrument the agent creation and invocation
+    if (exports.createReactAgent && typeof exports.createReactAgent === 'function') {
+      const originalCreateReactAgent = exports.createReactAgent;
+      Object.defineProperty(exports, 'createReactAgent', {
+        value: instrumentCreateReactAgent(originalCreateReactAgent as (...args: unknown[]) => CompiledGraph, options),
+        writable: true,
+        enumerable: true,
+        configurable: true,
+      });
+    }
+
     return exports;
   }
 }