Plugin Packaging

Plugin Packaging

Claude Code plugins are directory bundles installable via claude plugin install <name>@<marketplace> or /plugin marketplace add <git-url-or-path>.

Required layout

my-plugin/
├── .claude-plugin/
│   ├── plugin.json          # manifest (only required file for a manifest-driven plugin)
│   └── marketplace.json     # if you're shipping a marketplace in this repo
├── skills/<name>/SKILL.md
├── commands/<ns>/<cmd>.md
├── agents/<agent>.md
├── hooks/hooks.json         # optional
├── .mcp.json                # optional
├── scripts/                 # helpers invoked by hooks/agents
├── bin/                     # binaries added to PATH inside the plugin sandbox
├── README.md
├── LICENSE
└── CHANGELOG.md

Critical: components must live at the plugin root, not inside .claude-plugin/.

plugin.json minimum

{
  "name": "my-plugin",
  "version": "0.1.0",
  "description": "…",
  "author": {"name": "…", "email": "…"},
  "license": "MIT"
}

If you follow default layout, Claude Code auto-discovers skills/agents/commands/hooks/MCPs. Only set "skills", "commands", "agents" keys if you use custom paths.

Path substitution

• ${CLAUDE_PLUGIN_ROOT} — absolute path to the plugin (changes on update; don't write persistent files here).
• ${CLAUDE_PLUGIN_DATA} — ~/.claude/plugins/data/<id>/, persists across updates. Use for caches, node_modules, venvs, generated state.

Use these in hook commands, MCP configs, and @-imports inside commands/agents/skills.

marketplace.json

{
  "name": "my-marketplace",
  "owner": {"name": "…"},
  "plugins": [
    {
      "name": "my-plugin",
      "source": "./",
      "description": "…",
      "version": "0.1.0"
    }
  ]
}

source can be a local path or a git URL. Users install via /plugin marketplace add <path-or-url> then claude plugin install my-plugin@my-marketplace.

userConfig (prompted at install)

{
  "userConfig": {
    "api_token": {"description": "Your API token", "sensitive": true},
    "workspace_id": {"description": "Workspace ID", "sensitive": false}
  }
}

Non-sensitive values are substitutable as ${user_config.KEY}; sensitive go to keychain. Exported as CLAUDE_PLUGIN_OPTION_<KEY> to subprocesses.

Security constraints for plugin-shipped agents

hooks, mcpServers, permissionMode are NOT permitted in plugin agent frontmatter. Keep these at the plugin level only.

Validation

claude plugin validate ./my-plugin
# or inside Claude Code:
/plugin validate

Checks manifest syntax, frontmatter on skills/agents/commands, hooks.json schema.

Versioning

SemVer. Bump version in plugin.json on every public change — Claude Code caches by version; unchanged version = users don't see updates. Maintain CHANGELOG.md.

References

• @../../agents-architect/references/plugin-manifest.md — full field reference
• @../../agents-architect/templates/plugin.json.template
• @../../agents-architect/templates/marketplace.json.template

Output

When packaging:

1. Create .claude-plugin/plugin.json + optionally marketplace.json.
2. Verify layout (components at root, not in .claude-plugin/).
3. Run claude plugin validate and fix errors.
4. Write CHANGELOG entry + bump version.
5. Produce install instructions for README.