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

# Anthropic SDK (Python)

> Capture traces from the Anthropic Python SDK with OpenInference

## Install

```bash theme={null}
pip install anthropic openinference-instrumentation-anthropic \
            opentelemetry-sdk opentelemetry-exporter-otlp-proto-http
```

## Setup

<Note>
  Anthropic traces can include input messages, output messages, tool names, and tool parameters. Review [Data Governance](/data-governance) before enabling production traffic.
</Note>

```python theme={null}
import os
from anthropic import Anthropic
from openinference.instrumentation.anthropic import AnthropicInstrumentor
from openinference.instrumentation import using_attributes
from opentelemetry import trace
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.exporter.otlp.proto.http.trace_exporter import OTLPSpanExporter

os.environ["OTEL_EXPORTER_OTLP_ENDPOINT"] = "https://otel.agnost.ai"
os.environ["OTEL_EXPORTER_OTLP_HEADERS"] = "X-Agnost-Org-ID=<your-org-id>"

provider = TracerProvider()
provider.add_span_processor(BatchSpanProcessor(OTLPSpanExporter()))
trace.set_tracer_provider(provider)
AnthropicInstrumentor().instrument(tracer_provider=provider)

client = Anthropic()
with using_attributes(session_id="sess-123", user_id="u-42"):
    client.messages.create(
        model="claude-sonnet-4-5",
        max_tokens=1024,
        messages=[{"role": "user", "content": "Hi"}],
    )
```

Tool-use blocks are unpacked. You get `llm.input_messages.*`, `llm.output_messages.*`, `tool.name`, `tool.parameters`, and `llm.token_count.{prompt,completion}`.

## Alternative

The Traceloop alternative (`opentelemetry-instrumentation-anthropic`) emits `gen_ai.*` and `traceloop.*`: also recognized by Agnost.

## Verify

Run one `client.messages.create` call, then open **Raw logs** in Agnost. Confirm message and tool-use attributes appear as expected.

## Troubleshooting

* Confirm `AnthropicInstrumentor().instrument(...)` runs before Anthropic calls.
* Confirm `OTEL_EXPORTER_OTLP_HEADERS` contains `X-Agnost-Org-ID=<your-org-id>`.
* Confirm `using_attributes` wraps the call you want grouped.

## References

* [Enable OpenTelemetry export](https://github.com/Arize-ai/openinference/tree/main/python/instrumentation/openinference-instrumentation-anthropic)
* [Add custom metadata](https://arize.com/docs/phoenix/tracing/how-to-tracing/add-metadata/customize-spans)