# GET /lastError

Read the last engine JavaScript error.

This is a device HTTP route. Set `DEVICE_URL` to your reachable device URL; [connection and examples](https://mcp.applesauceos.com/doc/http.md) explain how. Do not append this path to the public MCP URL.

## Parameters

No parameters.

## Response

JSON {lastError:string|null}.

## Example

```sh
curl --fail-with-body "$DEVICE_URL/lastError"
```

## Notes

Historical shared state, not proof of success or failure for your current run.

Check the HTTP status and any JSON error. [HTTP workflows and error handling](https://mcp.applesauceos.com/doc/http-guide.md) explain shared limits. [All endpoints](https://mcp.applesauceos.com/doc/http.md).