Trace LangChain & LangGraph Workflows with Veritrix

Veritrix plugs directly into LangChain and LangGraph with a single initialization call, giving you deep visibility into chains, agents, and stateful graphs without touching your existing application logic. Every LLM invocation, tool call, retriever lookup, and LangGraph node transition is captured as a structured trace and surfaced in the Veritrix dashboard — so you can debug failures, measure latency, and understand exactly how your graph executes at runtime.

Prerequisites

Python 3.9 or higher
An active Veritrix account and API key
LangChain and/or LangGraph installed

Installation & Setup

Install Veritrix alongside LangChain

pip install veritrix langchain langchain-openai

If you are using LangGraph, install it as well:

pip install langgraph

Initialize Veritrix tracing

Call trace.init() once at application startup, before you instantiate any LLM or chain.

from veritrix import trace

trace.init("langchain-agent")

Use LangChain and LangGraph as normal

Veritrix automatically instruments the LangChain callback system after trace.init(). No custom callbacks or wrappers are required.

from langchain_openai import ChatOpenAI
from veritrix import trace

trace.init("langchain-agent")
llm = ChatOpenAI(model="gpt-4o")
# Use llm normally — all calls are traced

Example: LangChain Chain

The following example builds a simple prompt-and-response chain. Veritrix traces the entire chain execution, including each LLM call and its token usage.

from langchain_openai import ChatOpenAI
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.output_parsers import StrOutputParser
from veritrix import trace

trace.init("langchain-agent")

llm = ChatOpenAI(model="gpt-4o")

prompt = ChatPromptTemplate.from_messages([
    ("system", "You are a concise technical writer."),
    ("human", "Summarize the following in two sentences: {text}"),
])

chain = prompt | llm | StrOutputParser()

result = chain.invoke({"text": "OpenTelemetry is a set of APIs, SDKs, and tools for instrumenting, generating, collecting, and exporting telemetry data."})
print(result)

Example: LangGraph Stateful Graph

For LangGraph workflows, Veritrix traces each node invocation and the edges traversed between them, giving you a step-by-step view of graph execution.

from langgraph.graph import StateGraph, END
from langchain_openai import ChatOpenAI
from veritrix import trace
from typing import TypedDict

trace.init("langgraph-pipeline")

llm = ChatOpenAI(model="gpt-4o")

class AgentState(TypedDict):
    question: str
    answer: str

def answer_node(state: AgentState) -> AgentState:
    response = llm.invoke(state["question"])
    return {"question": state["question"], "answer": response.content}

builder = StateGraph(AgentState)
builder.add_node("answer", answer_node)
builder.set_entry_point("answer")
builder.add_edge("answer", END)

graph = builder.compile()
output = graph.invoke({"question": "What is observability?", "answer": ""})
print(output["answer"])

What Gets Captured Automatically

Signal	Details
LLM calls	Model name, prompt messages, completion, token counts, latency
Tool calls	Tool name, input, output, duration
Retriever calls	Query, retrieved documents, relevance scores
LangGraph nodes	Node name, input state, output state, duration
Agent handoffs	Source agent, target agent, context forwarded
Retries	Retry attempt number, error type, delay

Veritrix hooks into LangChain’s native callback system under the hood. If you already use custom callbacks (for logging, streaming, etc.), they continue to work alongside Veritrix without conflict.

OpenTelemetry Compatibility

Veritrix is built on OpenTelemetry. Every span generated for your LangChain or LangGraph execution is a standards-compliant OTel span, exportable to any OTel-compatible backend — including collectors you already operate.

To send traces to your own OTel collector or a third-party observability platform, see the OpenTelemetry integration page.

Get Started

Core Concepts

Tutorials

Integrations

Features

Account & Billing

Trace LangChain & LangGraph Workflows with Veritrix

Prerequisites

Installation & Setup

Example: LangChain Chain

Example: LangGraph Stateful Graph

What Gets Captured Automatically

OpenTelemetry Compatibility

​Prerequisites

​Installation & Setup

​Example: LangChain Chain

​Example: LangGraph Stateful Graph

​What Gets Captured Automatically

​OpenTelemetry Compatibility

Prerequisites

Installation & Setup

Example: LangChain Chain

Example: LangGraph Stateful Graph

What Gets Captured Automatically

OpenTelemetry Compatibility