[aw] API Diff Worker failed

### Workflow Failure

**Workflow:** [API Diff Worker](https://github.com/dotnet/core/blob/main/.github/workflows/api-diff-worker.md)
**Branch:** main
**Run:** https://github.com/dotnet/core/actions/runs/34849338545

> [!WARNING]
> **Invalid or Unsupported Model**: The agent failed because the configured model name is invalid, unknown, or unavailable for this engine/account.

This is a **configuration issue**, not a transient error — retrying will not help.

How to fix this

Specify a valid model for the selected engine in the workflow frontmatter:

```yaml
---
engine: copilot
model: gpt-5-mini
---
```

To find valid models, check your engine/provider documentation (for Copilot see [supported models](https://docs.github.com/en/copilot/using-github-copilot/using-github-copilot-in-the-command-line#supported-models)).

> [!WARNING]
> **Engine Failure**: The `copilot` engine terminated unexpectedly.

**Last agent output:**
```
at _rmdirSync (node:internal/fs/rimraf:251:7)
at rimrafSync (node:internal/fs/rimraf:194:7)
at node:internal/fs/rimraf:254:9
at Array.forEach ()
at _rmdirSync (node:internal/fs/rimraf:251:7) {
errno: -13,
code: 'EACCES',
syscall: 'unlink',
path: '/tmp/awf-1789393286756-chroot-home/.aws/config'
}
```

### Action Required

**Assign this issue to an agent** to debug and fix the issue.

Debug with any coding agent

Use this prompt with any coding agent (GitHub Copilot, Claude, Gemini, etc.):

````
Debug the agentic workflow failure using https://raw.githubusercontent.com/github/gh-aw/main/debug.md

The failed workflow run is at https://github.com/dotnet/core/actions/runs/34849338545
````

Manually invoke the agent

Debug this workflow failure using your favorite Agent CLI and the `agentic-workflows` prompt.

- Start your agent
- Load the `agentic-workflows` skill from `.github/skills/agentic-workflows/SKILL.md` or
- Type `debug the agentic workflow api-diff-worker failure in https://github.com/dotnet/core/actions/runs/34849338545`

> [!TIP]
>
> Stop reporting this workflow as a failure
>
> To stop a workflow from creating failure issues, set `report-failure-as-issue: false` in its frontmatter:
> ```yaml
> safe-outputs:
> report-failure-as-issue: false
> ```
>
>

> Generated from [API Diff Worker](https://github.com/dotnet/core/actions/runs/34849338545) · [◷](https://github.com/search?q=repo%3Adotnet%2Fcore+is%3Aissue+%22gh-aw-workflow-id%3A+api-diff-worker%22&type=issues)
> - [x] expires on Sep 21, 2026, 1:45 PM UTC

Read .github/workflows/api-diff-worker.md and the referenced failed run first, then review the agentic-workflows guidance in .github/skills/agentic-workflows/SKILL.md. Trace both the invalid model configuration and the reported filesystem failure. Done means the API Diff Worker completes successfully without creating a failure issue.

Written by the indexing model from the issue text.