--- description: Start here to integrate Opik into your LangGraph-based genai application for end-to-end LLM observability, unit testing, and optimization. headline: LangGraph | Opik Documentation og:description: Capture detailed insights of your LangGraph applications effortlessly with Opik's integration for logging and tracing during development and production. og:site_name: Opik Documentation og:title: Integrate LangGraph with Opik for Seamless Tracing title: Observability for LangGraph with Opik --- Opik provides a seamless integration with LangGraph, allowing you to easily log and trace your LangGraph-based applications. By using the `OpikTracer` callback, you can automatically capture detailed information about your LangGraph graph executions during both development and production. ## Account Setup [Comet](https://www.comet.com/site?from=llm&utm_source=opik&utm_medium=colab&utm_content=langgraph&utm_campaign=opik) provides a hosted version of the Opik platform, [simply create an account](https://www.comet.com/signup?from=llm&utm_source=opik&utm_medium=colab&utm_content=langgraph&utm_campaign=opik) and grab your API Key. > You can also run the Opik platform locally, see the [installation guide](https://www.comet.com/docs/opik/self-host/overview/?from=llm&utm_source=opik&utm_medium=colab&utm_content=langgraph&utm_campaign=opik) for more information. ## Getting Started ### Installation To use the [`OpikTracer`](https://www.comet.com/docs/opik/python-sdk-reference/integrations/langchain/OpikTracer.html) with LangGraph, you'll need to have both the `opik` and `langgraph` packages installed. You can install them using pip: ```bash pip install opik langgraph langchain ``` ### Configuring Opik Configure the Opik Python SDK for your deployment type. See the [Python SDK Configuration guide](/tracing/advanced/sdk_configuration) for detailed instructions on: - **CLI configuration**: `opik configure` - **Code configuration**: `opik.configure()` - **Self-hosted vs Cloud vs Enterprise** setup - **Configuration files** and environment variables ## Using Opik with LangGraph Opik provides two ways to track LangGraph applications. We recommend using the `track_langgraph` function for a simpler experience, but you can also use the `OpikTracer` callback directly if you need more control. ### Option 1: Using `track_langgraph` (Recommended) The simplest way to track your LangGraph applications is using the [`track_langgraph`](https://www.comet.com/docs/opik/python-sdk-reference/integrations/langchain/track_langgraph.html) function. This function wraps your compiled graph once, and all subsequent invocations are automatically tracked without needing to pass callbacks: ```python from typing import List, Annotated from pydantic import BaseModel from opik.integrations.langchain import OpikTracer, track_langgraph from langchain_core.messages import HumanMessage from langgraph.graph import StateGraph, START, END from langgraph.graph.message import add_messages # create your LangGraph graph class State(BaseModel): messages: Annotated[list, add_messages] def chatbot(state): # Typically your LLM calls would be done here return {"messages": "Hello, how can I help you today?"} graph = StateGraph(State) graph.add_node("chatbot", chatbot) graph.add_edge(START, "chatbot") graph.add_edge("chatbot", END) app = graph.compile() # Create OpikTracer and track the graph once - no need to pass callbacks anymore! # The graph visualization is automatically extracted by track_langgraph opik_tracer = OpikTracer( tags=["production"], metadata={"version": "1.0"} ) app = track_langgraph(app, opik_tracer) # Now all invocations are automatically tracked for s in app.stream({"messages": [HumanMessage(content = "How to use LangGraph ?")]}): print(s) # No callbacks needed here either! result = app.invoke({"messages": [HumanMessage(content = "How to use LangGraph ?")]}) ``` This is similar to how other Opik integrations work (like OpenAI, Anthropic, etc.), where you wrap the client or object once and then use it normally. ### Option 2: Using `OpikTracer` callback If you need more fine-grained control or want to use different tracers for different invocations, you can use the [`OpikTracer`](https://www.comet.com/docs/opik/python-sdk-reference/integrations/langchain/OpikTracer.html) callback directly: ```python from typing import List, Annotated from pydantic import BaseModel from opik.integrations.langchain import OpikTracer from langchain_core.messages import HumanMessage from langgraph.graph import StateGraph, START, END from langgraph.graph.message import add_messages # create your LangGraph graph class State(BaseModel): messages: Annotated[list, add_messages] def chatbot(state): # Typically your LLM calls would be done here return {"messages": "Hello, how can I help you today?"} graph = StateGraph(State) graph.add_node("chatbot", chatbot) graph.add_edge(START, "chatbot") graph.add_edge("chatbot", END) app = graph.compile() # Create the OpikTracer opik_tracer = OpikTracer() # Pass the OpikTracer callback to each invocation for s in app.stream({"messages": [HumanMessage(content = "How to use LangGraph ?")]}, config={"callbacks": [opik_tracer]}): print(s) result = app.invoke({"messages": [HumanMessage(content = "How to use LangGraph ?")]}, config={"callbacks": [opik_tracer]}) ``` ### Viewing Traces in the UI Once tracking is enabled using either method, you will start to see the traces in the Opik UI: ## Practical Example: Classification Workflow Let's walk through a real-world example of using LangGraph with Opik for a classification workflow. This example demonstrates how to create a graph with conditional routing and track its execution. ### Setting up the Environment First, let's set up our environment with the necessary dependencies: ```python import opik # Configure Opik opik.configure(use_local=False) ``` ### Creating the LangGraph Workflow We'll create a LangGraph workflow with 3 nodes that demonstrates conditional routing: ```python from langgraph.graph import StateGraph, END from typing import TypedDict, Optional # Define the graph state class GraphState(TypedDict): question: Optional[str] = None classification: Optional[str] = None response: Optional[str] = None # Create the node functions def classify(question: str) -> str: return "greeting" if question.startswith("Hello") else "search" def classify_input_node(state): question = state.get("question", "").strip() classification = classify(question) return {"classification": classification} def handle_greeting_node(state): return {"response": "Hello! How can I help you today?"} def handle_search_node(state): question = state.get("question", "").strip() search_result = f"Search result for '{question}'" return {"response": search_result} # Create the workflow workflow = StateGraph(GraphState) workflow.add_node("classify_input", classify_input_node) workflow.add_node("handle_greeting", handle_greeting_node) workflow.add_node("handle_search", handle_search_node) # Add conditional routing def decide_next_node(state): return ( "handle_greeting" if state.get("classification") == "greeting" else "handle_search" ) workflow.add_conditional_edges( "classify_input", decide_next_node, {"handle_greeting": "handle_greeting", "handle_search": "handle_search"}, ) workflow.set_entry_point("classify_input") workflow.add_edge("handle_greeting", END) workflow.add_edge("handle_search", END) app = workflow.compile() ``` ### Executing with Opik Tracing Now let's execute the workflow with Opik tracing enabled using `track_langgraph`: ```python from opik.integrations.langchain import OpikTracer, track_langgraph # Create OpikTracer and track the graph once # The graph visualization is automatically extracted by track_langgraph opik_tracer = OpikTracer( project_name="classification-workflow" ) app = track_langgraph(app, opik_tracer) # Execute the workflow - no callbacks needed! inputs = {"question": "Hello, how are you?"} result = app.invoke(inputs) print(result) # Test with a different input - still tracked automatically inputs = {"question": "What is machine learning?"} result = app.invoke(inputs) print(result) ``` The graph execution is now logged on the Opik platform and can be viewed in the UI. The trace will show the complete execution path through the graph, including the classification decision and the chosen response path. ## Compatibility with Opik tracing context LangGraph tracing integrates seamlessly with Opik's tracing context, allowing you to call `@track`-decorated functions (and most use most of other native Opik integrations) from within your graph nodes and have them automatically attached to the trace tree. ### Synchronous execution (invoke) For synchronous graph execution using `invoke()`, everything works out of the box. You can access current spans/traces from LangGraph nodes and call tracked functions inside them: ```python import opik_context from opik import track from opik.integrations.langchain import OpikTracer, track_langgraph from langgraph.graph import StateGraph, START, END @track def process_data(value: int) -> int: """Custom tracked function that will be attached to the trace tree.""" return value * 2 def my_node(state): current_trace_data = opik_context.get_current_trace_data() current_span_data = opik_context.get_current_span_data() # will return the span for `my_node`, created by OpikTracer # This tracked function call will automatically be part of the trace tree result = process_data(state["value"]) return {"value": result} # Build and execute graph graph = StateGraph(dict) graph.add_node("processor", my_node) graph.add_edge(START, "processor") graph.add_edge("processor", END) app = graph.compile() opik_tracer = OpikTracer() app = track_langgraph(app, opik_tracer) # Synchronous execution - tracked functions work automatically result = app.invoke({"value": 21}) ``` ### Asynchronous execution (ainvoke) For asynchronous graph execution using `ainvoke()`, you need to explicitly propagate the trace context to `@track`-decorated functions using the `extract_current_langgraph_span_data` helper: This is due to a LangChain framework limitation that doesn't automatically share the execution context between callbacks (like `OpikTracer`) and node code in async scenarios. The explicit trace context propagation via distributed headers is required for seamless tracking across async boundaries. ```python from opik import track from opik.integrations.langchain import OpikTracer, track_langgraph, extract_current_langgraph_span_data from langgraph.graph import StateGraph, START, END @track def process_data(value: int) -> int: """Custom tracked function that needs distributed trace headers in async context.""" return value * 2 async def my_async_node(state, config): # Extract current span data from LangGraph config. `opik_context` doesn't work here due to langgraph platform limitations related to context propagation. span_data = extract_current_langgraph_span_data(config) # Pass distributed trace headers to attach the tracked function to the trace tree result = process_data( state["value"], opik_distributed_trace_headers=span_data.get_distributed_trace_headers() # all tracked functions implicitly support this parameter ) return {"value": result} # Build and execute graph graph = StateGraph(dict) graph.add_node("processor", my_async_node) graph.add_edge(START, "processor") graph.add_edge("processor", END) app = graph.compile() opik_tracer = OpikTracer() app = track_langgraph(app, opik_tracer) # Asynchronous execution - requires explicit trace context propagation result = await app.ainvoke({"value": 21}) ``` Alternatively, if you don't want to use the `@track` decorator, you can use the `opik.start_as_current_span` context manager with distributed headers: ```python import opik from opik.integrations.langchain import OpikTracer, track_langgraph, extract_current_langgraph_span_data from langgraph.graph import StateGraph, START, END async def my_async_node(state, config): span_data = extract_current_langgraph_span_data(config) # Use context manager with distributed headers with opik.start_as_current_span( name="custom_operation", input={"input": state["value"]}, opik_distributed_trace_headers=span_data.get_distributed_trace_headers() ) as span_data: # Your custom logic here result = state["value"] * 2 span_data.output = {"output": result} return {"value": result} # Build and execute graph graph = StateGraph(dict) graph.add_node("processor", my_async_node) graph.add_edge(START, "processor") graph.add_edge("processor", END) app = graph.compile() opik_tracer = OpikTracer() app = track_langgraph(app, opik_tracer) result = await app.ainvoke({"value": 21}) ``` ## Logging threads When you are running multi-turn conversations using [LangGraph persistence](https://langchain-ai.github.io/langgraph/concepts/persistence/#threads), Opik will use Langgraph's thread_id as Opik thread_id. Here is an example below: ```python import sqlite3 from langgraph.checkpoint.sqlite import SqliteSaver from typing import Annotated from pydantic import BaseModel from opik.integrations.langchain import OpikTracer, track_langgraph from langchain_core.messages import HumanMessage from langgraph.graph import StateGraph, START, END from langgraph.graph.message import add_messages from langchain.chat_models import init_chat_model llm = init_chat_model("openai:gpt-4.1") # create your LangGraph graph class State(BaseModel): messages: Annotated[list, add_messages] def chatbot(state): # Typically your LLM calls would be done here return {"messages": [llm.invoke(state.messages)]} graph = StateGraph(State) graph.add_node("chatbot", chatbot) graph.add_edge(START, "chatbot") graph.add_edge("chatbot", END) # Create a new SqliteSaver instance # Note: check_same_thread=False is OK as the implementation uses a lock # to ensure thread safety. conn = sqlite3.connect("checkpoints.sqlite", check_same_thread=False) memory = SqliteSaver(conn) app = graph.compile(checkpointer=memory) # Create the OpikTracer and track the graph opik_tracer = OpikTracer() app = track_langgraph(app, opik_tracer) thread_id = "e424a45e-7763-443a-94ae-434b39b67b72" config = {"configurable": {"thread_id": thread_id}} # Initialize the state state = State(**app.get_state(config).values) or State(messages=[]) print("STATE", state) # Add the user message state.messages.append(HumanMessage(content="Hello, my name is Bob, how are you doing ?")) # state.messages.append(HumanMessage(content="What is my name ?")) result = app.invoke(state, config=config) print("Result", result) ``` ## Updating logged traces You can use the [`OpikTracer.created_traces`](https://www.comet.com/docs/opik/python-sdk-reference/integrations/langchain/OpikTracer.html#opik.integrations.langchain.OpikTracer.created_traces) method to access the trace IDs collected by the OpikTracer callback: ```python from opik.integrations.langchain import OpikTracer opik_tracer = OpikTracer() # Calling LangGraph stream or invoke functions traces = opik_tracer.created_traces() print([trace.id for trace in traces]) ``` These can then be used with the [`Opik.log_traces_feedback_scores`](https://www.comet.com/docs/opik/python-sdk-reference/Opik.html#opik.Opik.log_traces_feedback_scores) method to update the logged traces. ## Advanced usage The `OpikTracer` object has a `flush` method that can be used to make sure that all traces are logged to the Opik platform before you exit a script. This method will return once all traces have been logged or if the timeout is reach, whichever comes first. ```python from opik.integrations.langchain import OpikTracer opik_tracer = OpikTracer() opik_tracer.flush() ```