plugin-creator

Plugin Creator is a scaffolding skill for building Codex plugins. It solves the boilerplate problem of standing up a correctly-structured plugin directory: it always produces the required `.codex-plugin/plugin.json` manifest with the full schema shape, placeholder values, and the complete `interface` section, so authors can fill in `[TODO: ...]` placeholders rather than assembling the layout by hand. It can also generate or update the repo-root `.agents/plugins/marketplace.json` that controls plugin ordering and availability metadata in the Codex UI.

The skill drives a bundled Python script, `scripts/create_basic_plugin.py`, that normalizes the plugin name to lower-case hyphen-case, creates the plugin root and manifest, and optionally scaffolds companion folders (`skills/`, `hooks/`, `scripts/`, `assets/`, `.mcp.json`, `.app.json`) via flags such as `--with-skills` and `--with-marketplace`. It supports both repo-local and home-local plugin locations, asking the user which they want before generating marketplace entries. Marketplace entries default to `policy.installation: AVAILABLE` and `policy.authentication: ON_INSTALL`, always include a category, and are appended rather than reordered unless the user asks otherwise. A reference spec documents every manifest and marketplace field.

It targets plugin developers and teams publishing to a Codex marketplace who want consistent, spec-conformant plugin scaffolding and correctly-formed availability metadata. Use cases include creating a new local plugin, adding optional plugin structure to an existing one, and registering a plugin in the marketplace catalog.