> ## Documentation index
> Fetch the complete documentation index at: https://arize.com/llms.txt
> Ask it with GET https://arize.com/ask?q=<keywords or question>. Short keywords rank best.
> Use these to discover all available pages before exploring further.

# Cohere Tracing

> Instrument LLM calls made using Cohere's Python client via the CohereInstrumentor

Cohere builds enterprise-grade large language models for chat, search, and retrieval-augmented generation. The Cohere Python client can be instrumented using the [`openinference-instrumentation-cohere`](https://github.com/Arize-ai/openinference/tree/main/python/instrumentation/openinference-instrumentation-cohere) package.

## Install

```bash
pip install openinference-instrumentation-cohere cohere
```

The instrumentor requires `cohere >= 5.13.0`.

## Setup

Set the `CO_API_KEY` environment variable to authenticate calls made using the client.

```bash
export CO_API_KEY=[your_key_here]
```

Connect your application to Phoenix with the `register` function, then enable the `CohereInstrumentor`:

```python
from openinference.instrumentation.cohere import CohereInstrumentor
from phoenix.otel import register

# configure the Phoenix tracer
tracer_provider = register(project_name="my-llm-app")

CohereInstrumentor().instrument(tracer_provider=tracer_provider)
```

## Run Cohere

```python
import cohere

co = cohere.ClientV2()
response = co.chat(
    model="command-a-03-2025",
    messages=[{"role": "user", "content": "Why is the sky blue?"}],
)
print(response.message.content[0].text)
```

## Observe

Now that you have tracing setup, all chat calls made with the Cohere v2 client will be streamed to your running Phoenix for observability and evaluation. Spans capture the input messages, output message, invocation parameters, tool definitions and tool calls, and token counts from Cohere's `usage.tokens`.

## Coverage

The instrumentor traces the Cohere **v2** client (`cohere.ClientV2` and `cohere.AsyncClientV2`), covering both the `chat` and `chat_stream` methods. Streamed calls finish their span when the returned iterator is exhausted, with the accumulated output message, tool calls, and token counts.

The following are **not** traced and produce no spans:

* The v1 client (`cohere.Client`)
* The embed, rerank, and classify endpoints

## Resources

* [Example chat script](https://github.com/Arize-ai/openinference/blob/main/python/instrumentation/openinference-instrumentation-cohere/examples/chat.py)

* [OpenInference package](https://github.com/Arize-ai/openinference/tree/main/python/instrumentation/openinference-instrumentation-cohere)