[Bug]: Skills and agents not available when installed via `copilot plugin install microsoft/WinAppCli`

[Megasware128]

Describe the bug

Following the recommended installation instructions for AI coding agents from the README:

copilot plugin install microsoft/WinAppCli

The plugin installs successfully and is registered in ~/.copilot/config.json with enabled: true. However, none of the winapp-cli skills or agents are available in the Copilot CLI session.

The Copilot CLI sets cache_path to the downloaded repository root (~/.copilot/installed-plugins/_direct/microsoft--WinAppCli), but the plugin definition (plugin.json, skills, and agents) lives inside .github/plugin/. The plugin loader expects plugin.json at the root of cache_path and never finds it.

To Reproduce

1. Run copilot plugin install microsoft/WinAppCli
2. Start a new Copilot CLI session
3. Ask the agent to use winapp skills (e.g. "help me create an MSIX package")
4. Observe: skills are not available, agent does not have winapp knowledge
5. Inspect ~/.copilot/config.json — plugin is registered with cache_path pointing to repo root

Expected behavior

After running copilot plugin install microsoft/WinAppCli, all winapp-cli skills (setup, signing, packaging, identity, manifest, frameworks, troubleshoot) and the winapp agent should be available in the Copilot CLI session.

Workaround: Manually edit ~/.copilot/config.json and append /.github/plugin to the cache_path:

"cache_path": "...\\microsoft--WinAppCli\\.github\\plugin"

After restarting the Copilot CLI, all skills and the agent are correctly loaded.

Possible fixes from this repo's side:

1. Update README to recommend copilot plugin install microsoft/WinAppCli:.github/plugin (if supported per Installing plugins from a specific branch or tag github/copilot-cli#1296)
2. Add a root-level plugin.json that redirects or duplicates .github/plugin/plugin.json
3. Coordinate with the Copilot CLI team to handle .github/plugin/ discovery automatically

Screenshots

N/A — this is a configuration/loading issue, no visual output.

OS Version and details

Windows 11, Copilot CLI 1.0.12, winapp-cli plugin v0.2.1

Cross-repo notice

This issue has also been filed as github/copilot-cli#2390 since the root cause may be in the Copilot CLI's plugin loader (not checking .github/plugin/ for plugin.json). It is unclear whether the fix should be in the Copilot CLI, in this repo (restructuring or adding a root-level plugin.json), or in both. Filing on both repos so the respective maintainers can determine the best course of action.

Related

• Copilot CLI issue: copilot plugin install from GitHub repo does not discover .github/plugin/plugin.json — skills and agents unavailable github/copilot-cli#2390
• Install syntax feature: Installing plugins from a specific branch or tag github/copilot-cli#1296 (owner/repo:path syntax which could be an alternative)

[nmetulev]

#365 should fix this (though it does seem like a recent change in copilot as it was working before)