# Introduction

[![PyPI](https://img.shields.io/pypi/v/fiddler-langgraph)](https://pypi.org/project/fiddler-langgraph/)

## Overview

Complete API reference documentation for the `fiddler-langgraph` package, which instruments [LangGraph](https://langchain-ai.github.io/langgraph/) (and the underlying LangChain callback system) and exports OpenTelemetry traces to Fiddler.

```bash
pip install fiddler-langgraph
```

```python
from fiddler_langgraph import LangGraphInstrumentor
```

## Components

### Instrumentation

Native LangGraph APIs for tracing, attributes, and LLM context. `LangGraphInstrumentor` patches the LangChain callback manager so all LangGraph runs emit Fiddler spans. `add_span_attributes` attaches component-scoped attributes to a specific model, retriever, or tool. `set_llm_context` and `clear_llm_context` attach and remove retrieval context (e.g. retrieved documents) on the active model so it appears on its LLM spans. `add_session_attributes` adds an attribute that appears on every span in the current context, and `set_conversation_id` (re-exported from `fiddler-otel`) tags all spans in the current context with a conversation ID.

* [add\_session\_attributes](/api/fiddler-langgraph-sdk/instrumentation/add-session-attributes.md)
* [add\_span\_attributes](/api/fiddler-langgraph-sdk/instrumentation/add-span-attributes.md)
* [clear\_llm\_context](/api/fiddler-langgraph-sdk/instrumentation/clear-llm-context.md)
* [LangGraphInstrumentor](/api/fiddler-langgraph-sdk/instrumentation/lang-graph-instrumentor.md)
* [set\_conversation\_id](/api/fiddler-langgraph-sdk/instrumentation/set-conversation-id.md)
* [set\_llm\_context](/api/fiddler-langgraph-sdk/instrumentation/set-llm-context.md)

### Re Exported From Otel

`fiddler-langgraph` re-exports the core `fiddler-otel` symbols so you only need to install one package. See the [Fiddler OTel SDK reference](/api/fiddler-otel-sdk/otel.md) for full details on each: `FiddlerClient` (the global client; required to construct `LangGraphInstrumentor`), `trace` (decorator that starts a Fiddler span around any function), `get_current_span` (return the active Fiddler span if any), `get_client` (return the global `FiddlerClient` instance), and the manual span wrappers `FiddlerChain`, `FiddlerGeneration`, `FiddlerSpan`, and `FiddlerTool`.

* [FiddlerChain](/api/fiddler-langgraph-sdk/re-exported-from-otel/fiddler-chain.md)
* [FiddlerClient](/api/fiddler-langgraph-sdk/re-exported-from-otel/fiddler-client.md)
* [FiddlerGeneration](/api/fiddler-langgraph-sdk/re-exported-from-otel/fiddler-generation.md)
* [FiddlerSpan](/api/fiddler-langgraph-sdk/re-exported-from-otel/fiddler-span.md)
* [FiddlerTool](/api/fiddler-langgraph-sdk/re-exported-from-otel/fiddler-tool.md)
* [get\_client](/api/fiddler-langgraph-sdk/re-exported-from-otel/get-client.md)
* [get\_current\_span](/api/fiddler-langgraph-sdk/re-exported-from-otel/get-current-span.md)
* [trace](/api/fiddler-langgraph-sdk/re-exported-from-otel/trace.md)


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