LangChain Tracing

Phoenix has first-class support for LangChain applications.

Install

pip install openinference-instrumentation-langchain langchain_openai

Setup

Connect your application to Phoenix with the register function:

Run LangChain

By instrumenting LangChain, spans will be created whenever a chain is run and will be sent to the Phoenix server for collection.

from langchain_core.prompts import ChatPromptTemplate
from langchain_openai import ChatOpenAI

prompt = ChatPromptTemplate.from_template("{x} {y} {z}?").partial(x="why is", z="blue")
chain = prompt | ChatOpenAI(model_name="gpt-3.5-turbo")
chain.invoke(dict(y="sky"))

Observe

Now that you have tracing setup, all invocations of chains will be streamed to your running Phoenix for observability and evaluation.

Resources

Example notebook
OpenInference package
Working examples

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LangChain Tracing

Install

Setup

Run LangChain

Observe

Resources

​Install

​Setup

​Run LangChain

​Observe

​Resources

Install

Setup

Run LangChain

Observe

Resources