feat(core): Instrument langgraph createReactAgent by andreiborza · Pull Request #20344 · getsentry/sentry-javascript

andreiborza · 2026-04-16T09:14:40Z

This PR adds instrumentation for LangGraph's createReactAgent API.

createReactAgent wrapping

Extracts agent name, LLM model, and tools from params
Wraps compiled graph's invoke() with invoke_agent span
Wraps tool invoke() with execute_tool spans (name, type, description, arguments, result)
Injects LangChain callback handler + lc_agent_name + __sentry_langgraph__ metadata at invoke level for chat span creation and agent name propagation to all child spans
Suppresses StateGraph.compile instrumentation inside createReactAgent to avoid duplicate spans

LangChain callback handler improvements

Reads gen_ai.agent.name from metadata.lc_agent_name (convention from newer LangGraph createAgent, adopted for our supported versions)
Suppresses chain and tool callback spans inside agent context (based on metadata.__sentry_langgraph__ presence) to avoid duplicates with our direct instrumentation
Extracts tool definitions from extraParams in handleChatModelStart and sets gen_ai.request.available_tools on chat spans
Uses runName for tool name in handleToolStart (set by LangChain's StructuredTool.call()) — fixes unknown_tool issue
Adds gen_ai.operation.name to tool spans
Extracts .content from ToolMessage objects in handleToolEnd instead of serializing the full wrapper
addToolCallsAttributes now prefers message.tool_calls (LangChain's normalized format) over scanning message.content for Anthropic-style tool_use items, fixing duplicate tool calls on Anthropic chat spans. Falls back to message.content scanning for older LangChain versions.

OTel module patching

Patches @langchain/langgraph/prebuilt for createReactAgent (ESM + CJS file patches for dist/prebuilt/index.cjs)

Exports

instrumentCreateReactAgent from core, browser, cloudflare

Closes: #19372

github-actions · 2026-04-16T10:52:57Z

size-limit report 📦

Path	Size	% Change	Change
@sentry/browser	26.16 kB	-	-
@sentry/browser - with treeshaking flags	24.63 kB	-	-
@sentry/browser (incl. Tracing)	44.11 kB	-	-
@sentry/browser (incl. Tracing + Span Streaming)	46.16 kB	-	-
@sentry/browser (incl. Tracing, Profiling)	49.06 kB	-	-
@sentry/browser (incl. Tracing, Replay)	83.46 kB	-	-
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	72.94 kB	-	-
@sentry/browser (incl. Tracing, Replay with Canvas)	88.14 kB	-	-
@sentry/browser (incl. Tracing, Replay, Feedback)	100.79 kB	-	-
@sentry/browser (incl. Feedback)	43.4 kB	-	-
@sentry/browser (incl. sendFeedback)	30.96 kB	-	-
@sentry/browser (incl. FeedbackAsync)	36.14 kB	-	-
@sentry/browser (incl. Metrics)	27.44 kB	-	-
@sentry/browser (incl. Logs)	27.59 kB	-	-
@sentry/browser (incl. Metrics & Logs)	28.28 kB	-	-
@sentry/react	27.9 kB	-	-
@sentry/react (incl. Tracing)	46.35 kB	-	-
@sentry/vue	31.03 kB	-	-
@sentry/vue (incl. Tracing)	45.95 kB	-	-
@sentry/svelte	26.18 kB	-	-
CDN Bundle	28.84 kB	-	-
CDN Bundle (incl. Tracing)	46.71 kB	-	-
CDN Bundle (incl. Logs, Metrics)	30.25 kB	-	-
CDN Bundle (incl. Tracing, Logs, Metrics)	47.8 kB	-	-
CDN Bundle (incl. Replay, Logs, Metrics)	69.34 kB	-	-
CDN Bundle (incl. Tracing, Replay)	83.88 kB	-	-
CDN Bundle (incl. Tracing, Replay, Logs, Metrics)	84.94 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback)	89.69 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics)	90.78 kB	-	-
CDN Bundle - uncompressed	84.55 kB	-	-
CDN Bundle (incl. Tracing) - uncompressed	139.68 kB	-	-
CDN Bundle (incl. Logs, Metrics) - uncompressed	88.75 kB	-	-
CDN Bundle (incl. Tracing, Logs, Metrics) - uncompressed	143.14 kB	-	-
CDN Bundle (incl. Replay, Logs, Metrics) - uncompressed	212.71 kB	-	-
CDN Bundle (incl. Tracing, Replay) - uncompressed	257.49 kB	-	-
CDN Bundle (incl. Tracing, Replay, Logs, Metrics) - uncompressed	260.93 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	271.18 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics) - uncompressed	274.62 kB	-	-
@sentry/nextjs (client)	48.84 kB	-	-
@sentry/sveltekit (client)	44.56 kB	-	-
@sentry/node-core	59 kB	+0.02%	+11 B 🔺
@sentry/node	171.08 kB	+0.58%	+979 B 🔺
@sentry/node - without tracing	97.81 kB	+0.02%	+12 B 🔺
@sentry/aws-serverless	114.53 kB	+0.05%	+49 B 🔺
@sentry/cloudflare (withSentry) - minified	164.13 kB	-	-
@sentry/cloudflare (withSentry)	415.2 kB	-	-

View base workflow run

Add instrumentation for LangGraph's `createReactAgent` API with full span hierarchy: invoke_agent, gen_ai.chat, and execute_tool. createReactAgent wrapping: - Extract agent name, LLM model, and tools from params - Wrap compiled graph's invoke() with invoke_agent span - Wrap tool invoke() with execute_tool spans (name, type, description, arguments, result) - Inject LangChain callback handler + lc_agent_name metadata at invoke level for chat span creation and agent name propagation to all child spans - Suppress StateGraph.compile instrumentation inside createReactAgent to avoid duplicate spans LangChain callback handler improvements: - Read gen_ai.agent.name from metadata.lc_agent_name - Suppress chain and tool callback spans inside agent context to avoid duplicates with our direct instrumentation - Extract tool definitions from extraParams in handleChatModelStart - Use runName for tool name (set by LangChain's StructuredTool) - Add gen_ai.operation.name to tool spans - Extract ToolMessage .content in handleToolEnd BREAKING: addToolCallsAttributes now reads from message.tool_calls (LangChain's normalized format) instead of scanning message.content for Anthropic-style tool_use items. This fixes duplicate tool calls on Anthropic chat spans but changes the tool call format in gen_ai.response.tool_calls from Anthropic-native to LangChain- normalized (args instead of input, type: tool_call instead of tool_use). OTel module patching: - Patch @langchain/langgraph/prebuilt for createReactAgent (ESM + CJS file patches for dist/prebuilt/index.cjs) Exports: - instrumentCreateReactAgent from core, browser, cloudflare Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

nicohrubec · 2026-04-29T07:22:23Z

 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';


h: So if I understand correctly right now users need instrumentCreateReactAgent for the agent and instrumentLangGraph for the StateGraph, right? I think now that we have the separate API instrumentLangGraph for the StateGraph might actually be a bit confusing, wdyt? I guess ideally what we would probably do is to merge this into one, detect what we are given and then handle the patching internally. Can we do this with the current approach?

This is certainly valid and a bit confusing. I do think it's better to have two functions here, these are for manual instrumenting, so it's clearer what they both do.
That being said, let's rename instrumentLangGraph to instrumentStateGraph as you suggested in #20584.

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nicohrubec

nice! thanks for the updates, lgtm

andreiborza requested a review from nicohrubec April 16, 2026 09:14

andreiborza force-pushed the ab/langgraph-agents branch from 6aa24b0 to 09a4132Compare April 16, 2026 10:43

andreiborza force-pushed the ab/langgraph-agents branch from 09a4132 to e2d8d45Compare April 16, 2026 14:44

andreiborza marked this pull request as ready for review April 20, 2026 04:09