Add a Windows ARM64 GitHub actions Python wheel builder agent

[finnagin]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• I have read and followed the Guidance for submissions involving paid services.
• My contribution adds a new instruction, prompt, agent, skill, or workflow file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, agent, skill, or workflow with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.
• I am targeting the staged branch for this pull request.

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Description

Now that the windows-11-arm image is generally available on GitHub actions many python projects have begun building and releasing Windows ARM64 wheels. Most of these projects simply need ci changes to enable these builds. This contribution would add an agent to assist Python package maintainers with adding Windows ARM64 wheel builds and tests to their existing GitHub actions workflows.

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Type of Contribution

• New instruction file.
• New prompt file.
• New agent file.
• New plugin.
• New skill file.
• New agentic workflow.
• Update to existing instruction, prompt, agent, plugin, skill, or workflow.
• Other (please specify):

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Additional Notes

• This agent has been tested and is retested each time a change is made to it on more than 15 python package repos including cryptography, safetensors, and pycurl.
• The agent handles many common build tools including cibuildwheel, maturin, and setuptools.
• While the agent is intended for workflow enablement and not for codebase refactoring, it has been tested on repos which required some source code changes to run on ARM64 Windows, and it has handled those cases correctly.
• The agent follows the structure of existing Windows x64 wheel build workflows to help guide its choices when implementing ARM64 wheel builds.

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[Copilot]

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[github-actions]

🟡 Contributor Reputation Check: MEDIUM risk

Check	Risk
Profile	MEDIUM
Credential audit	NONE

Maintainers: please review this contributor before merging.
See the workflow run for full details.
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[github-actions]

🔍 Skill Validator Results

⛔ Findings need attention

Scope	Checked
Skills	0
Agents	1
Total	1
Severity	Count
---	---:
❌ Errors	2
⚠️ Warnings	0
ℹ️ Advisories	0

Summary

Level	Finding
❌	[agent:GitHub Actions Windows ARM64 wheel builder] Agent name 'GitHub Actions Windows ARM64 wheel builder' does not match filename 'python-win-arm64-gha-wheel-builder.agent.md' (expected 'GitHub Actions Windows ARM64 wheel builder.agent.md').
❌	[agent:GitHub Actions Windows ARM64 wheel builder] Agent name 'GitHub Actions Windows ARM64 wheel builder' contains invalid characters — must be lowercase alphanumeric and hyphens only.

Full validator output

```text Found 1 agent(s) ❌ [agent:GitHub Actions Windows ARM64 wheel builder] Agent name 'GitHub Actions Windows ARM64 wheel builder' does not match filename 'python-win-arm64-gha-wheel-builder.agent.md' (expected 'GitHub Actions Windows ARM64 wheel builder.agent.md'). ❌ [agent:GitHub Actions Windows ARM64 wheel builder] Agent name 'GitHub Actions Windows ARM64 wheel builder' contains invalid characters — must be lowercase alphanumeric and hyphens only. Validated 1 agent(s)

{Ansi.Red}Agent spec conformance failures — fix the errors above.{Ansi.Reset}

</details>
> **Note:** The validator returned a non-zero exit code. Please review the findings above before merge.

[github-actions]

🟡 Contributor Reputation Check: MEDIUM risk

Check	Risk
Profile	MEDIUM
Credential audit	NONE

Maintainers: please review this contributor before merging.
See the workflow run for full details.
Automated check powered by AGT.

[aaronpowell]

Is an agent going to be the best choice for this, or would it be better to create a skill so that any agent could pick it up?

[github-actions]

🟡 Contributor Reputation Check: MEDIUM risk

Check	Risk
Profile	MEDIUM
Credential audit	NONE

Maintainers: please review this contributor before merging.
See the workflow run for full details.
Automated check powered by AGT.

[finnagin]

Hey @aaronpowell really sorry for the slow response on this, I've been in and out of the hospital the last couple weeks and may continue to be a bit slow to respond the next couple weeks too.

I've only ever used and tested it as an agent file but I think for most cases it would probably work well as a skill. The one thing that comes to mind for me is cases where a particular python package required a lot of complex changes to build an arm64 wheel it might be useful to have it run as an agent and work with another agent to loop through modifying the workflow/code and then pass it off to run a build and test the wheel/examine build logs. Though, to be fair, most packages require only ci changes and usually are able to be modified successfully in one pass.

What were your thoughts on it being better suited as a skill instead?