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

# Open WebUI

> Connect the Open WebUI self-hosted chat interface to Openference.

# Open WebUI

Open WebUI is a popular self-hosted AI chat interface. Connect it to Openference as an OpenAI-compatible endpoint.

## Add the connection

1. Open **Admin Settings → Connections**.
2. Add a new **OpenAI API** connection (or edit an existing one).
3. Set the Base URL and API key:

```
Base URL: https://api.openference.com/v1
API Key:  YOUR_API_KEY
```

4. Add a custom header in the connection's headers JSON:

```json theme={null}
{
  "User-Agent": "open-webui/openference"
}
```

5. Save the connection and select your Openference models in chat.

## The User-Agent header is required

Open WebUI does not send a distinctive User-Agent on outbound API calls — requests typically use a default Python HTTP client User-Agent, which is rejected with a 403 "coding agent required" error.

Adding the custom `User-Agent` header identifies your requests as coming from Open WebUI.

## Troubleshooting

* **403 coding agent required** — the custom User-Agent header is missing. Edit the connection and add the headers JSON shown above.
* **Models not appearing** — Open WebUI fetches `GET /v1/models` from the connection. Verify the base URL includes `/v1` and the key is valid.

See the [Compatibility Matrix](/integrations/compatibility-matrix) for an overview of all clients.