> ## Documentation Index
> Fetch the complete documentation index at: https://langwatch.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Haystack Instrumentation

> Learn how to instrument Haystack pipelines with LangWatch using community OpenTelemetry instrumentors.

LangWatch integrates with Haystack through OpenInference instrumentation to capture traces from your Haystack pipelines and components.

## Installation

<CodeGroup>
  ```bash pip theme={null}
  pip install langwatch openinference-instrumentation-haystack haystack-ai
  ```

  ```bash uv theme={null}
  uv add langwatch openinference-instrumentation-haystack haystack-ai
  ```
</CodeGroup>

## Usage

<Info>
  The LangWatch API key is configured by default via the `LANGWATCH_API_KEY` environment variable.
</Info>

Use the OpenInference instrumentation for Haystack by passing `HaystackInstrumentor` to `langwatch.setup()`.

```python  theme={null}
import os
import langwatch

from haystack.components.agents import Agent
from haystack.components.generators.chat import OpenAIChatGenerator
from haystack.dataclasses import ChatMessage
from openinference.instrumentation.haystack import HaystackInstrumentor

langwatch.setup(instrumentors=[HaystackInstrumentor()])

basic_agent = Agent(
    chat_generator=OpenAIChatGenerator(model="gpt-4o-mini"),
    system_prompt="You are a helpful web agent.",
    tools=[],
)

result = basic_agent.run(messages=[ChatMessage.from_user("Tell me a joke")])

print(result["last_message"].text)
```

The `HaystackInstrumentor` automatically captures Haystack pipeline operations, component executions, and model interactions. Use `@langwatch.trace()` to create a parent trace under which Haystack operations will be nested.

## Related

* [Capturing RAG](/integration/python/tutorials/capturing-rag) - Learn how to capture RAG data from retrievers and tools
* [Capturing Metadata and Attributes](/integration/python/tutorials/capturing-metadata) - Add custom metadata and attributes to your traces and spans
* [Capturing Evaluations & Guardrails](/integration/python/tutorials/capturing-evaluations-guardrails) - Log evaluations and implement guardrails in your Haystack applications