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

# Model settings

> The two switches in Open WebUI that silently break Computer Use if wrong.

After you add a model in Open WebUI, you **must** flip two settings. The managed `chat.yambr.com` does this by default; self-hosters running the bundled compose stack also get it done via `init.sh`. If you install Open WebUI yourself, or you add a new model after the initial setup, check these by hand.

| Setting              | Value    | Why                                                                                                                                                          |
| -------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Function Calling     | `Native` | Required for Computer Use tools to be invoked by the model. Without it, the model has no way to call `bash_tool`, `create_file`, etc. — it silently doesn't. |
| Stream Chat Response | `On`     | Enables real-time output streaming, including tool-call deltas. Without it, long-running tool sequences feel like the UI hung.                               |

## Set globally (recommended)

In **Admin → Settings → Models → Advanced Params**:

```
function_calling: native
stream_response: true
```

These become `DEFAULT_MODEL_PARAMS` — every model picks them up without per-model clicks. The bundled `init.sh` writes these on first Open WebUI startup:

```
POST /api/v1/configs/models
{
  "default_model_params": {
    "function_calling": "native",
    "stream_response": true
  }
}
```

## Set per model

If you want different behavior per model, override in the model's edit screen: **Workspace → Models → \[model] → Advanced Params**.

## Symptom: tools don't fire

If the model replies in plain text every time without calling tools, 99% of the time Function Calling is `Default` instead of `Native`. The `Default` path relies on Open WebUI's own tool-call parsing, which doesn't play well with MCP tools wired through the Computer Use tool module.

## Symptom: output hangs until complete

Stream Chat Response is `Off`. Turn it on; tool call output will appear as it's produced.