> ## Documentation Index
> Fetch the complete documentation index at: https://wb-21fd5541-wbdocs-1882.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# W&B Inference

> Access open-source foundation models through W&B Weave and an OpenAI-compatible API

W\&B Inference gives you access to leading open-source foundation models through W\&B Weave and an OpenAI-compatible API. You can:

* Build AI applications and agents without signing up for a hosting provider or self-hosting a model
* Try [supported models](/inference/models) in the [W\&B Weave Playground](/weave/guides/tools/playground)

With Weave, you can trace, evaluate, monitor, and improve your W\&B Inference-powered applications.

## Quickstart

Here's a simple example using Python:

```python theme={null}
import openai

client = openai.OpenAI(
    # The custom base URL points to W&B Inference
    base_url='https://api.inference.wandb.ai/v1',

    # Create an API key at https://wandb.ai/settings
    api_key="<your-api-key>",

    # Optional: Team and project for usage tracking
    project="<your-team>/<your-project>",
)

response = client.chat.completions.create(
    model="meta-llama/Llama-3.1-8B-Instruct",
    messages=[
        {"role": "system", "content": "You are a helpful assistant."},
        {"role": "user", "content": "Tell me a joke."}
    ],
)

print(response.choices[0].message.content)
```

## Next steps

1. Review the [available models](/inference/models) and [usage information and limits](/inference/usage-limits/)
2. Set up your account using the [prerequisites](/inference/prerequisites/)
3. Use the service through the [API](/inference/api-reference/) or [UI](/inference/ui-guide/)
4. Try the [usage examples](/inference/examples/)

## Usage details

<Info>
  For information about pricing, usage limits, and credits, see [Usage Information and Limits](/inference/usage-limits/).
</Info>