msd-core/docs/how-to/attach-a-plugin-skill-to-a-gsd-agent.md

How to attach a plugin-provided skill to a GSD agent

Use this guide when you have a Claude Code plugin that ships a skill and you want GSD agents to load it automatically at spawn time. The global:<plugin>:<skill> entry form makes GSD emit a Skill-tool load directive so the agent picks up the plugin skill alongside any project-local or personal global skills.

This feature works on the Claude runtime only. On other runtimes (Codex, Antigravity, Cursor, etc.) the entry is skipped with a warning. Plan accordingly if your team uses multiple runtimes.

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1. Install the plugin in Claude Code

GSD does not install or manage Claude Code plugins. Install the plugin first:

/plugin install <plugin-source>

Verify the plugin is active and note the skill names it exposes. The plugin's documentation or README will list available skill names in the format plugin:skill — for example, coderabbit:code-review.

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2. Find the namespaced skill name

The name you need has two colon-separated segments after global::

global:<plugin>:<skill>

For example, if the plugin slug is coderabbit and it provides a skill called code-review, the entry is:

global:coderabbit:code-review

Each segment must consist of alphanumeric characters, underscores, or hyphens only. No spaces, no slashes, no dots.

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3. Add the entry to agent_skills

Open .planning/config.json and add the namespaced skill to the array for the agent type that should receive it:

{
  "agent_skills": {
    "gsd-executor": [
      "skills/project-conventions",
      "global:coderabbit:code-review"
    ],
    "gsd-verifier": [
      "global:coderabbit:code-review"
    ]
  }
}

You can mix all three entry forms freely within the same array — project-relative paths, global:<name> personal skills, and global:<plugin>:<skill> plugin skills.

Or set it from the CLI:

gsd-tools query config-set agent_skills.gsd-executor '["skills/project-conventions","global:coderabbit:code-review"]'

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4. Verify the injection

Start a phase on the Claude runtime. When the target agent is spawned, its Task() prompt will contain an <agent_skills> block that includes a Skill-tool load directive for the plugin skill:

<agent_skills>
Read these user-configured skills:
- @skills/project-conventions/SKILL.md
- Load the `coderabbit:code-review` skill via the Skill tool before proceeding (plugin-provided).
</agent_skills>

Both entry types appear in the same Read these user-configured skills: section, interleaved in config order. There is no separate header for plugin-provided skills.

If you see [agent-skills] WARNING: Plugin-namespaced skill "global:coderabbit:code-review" requires a Skill-tool-capable runtime (claude) — skipping on runtime "<runtime>" in the logs, the entry is being skipped because the active runtime is not Claude. The configuration is still valid; no change is needed.

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Notes

• Plugin must be pre-installed. GSD only references the skill by namespaced name. If the plugin is not installed in Claude Code, the Skill tool call will fail at agent runtime — GSD cannot validate plugin presence at configuration time.
• Which agents support it. All 22 GSD agent types that consume agent_skills carry the Skill tool, so any of them can load plugin-provided skills. See Agent Skills Injection — Supported Agent Types for the full list.
• Non-Claude runtimes. The global:<plugin>:<skill> entry is silently skipped with a warning on non-Claude runtimes. Project-relative and global:<name> entries work on all runtimes.
• Security boundary. Plugin skill content is resolved entirely by Claude Code at agent runtime. GSD does not read, cache, or validate the plugin's files.

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Related

• Configuration — Agent Skills Injection
• Install a minimal GSD and add skills later
• Import a capability from a URL