# Plugin Creator > Create and scaffold plugin directories for Codex with a required `.codex-plugin/plugin.json`, optional plugin folders/files, valid manifest defaults, and personal-marketplace entries by default. Use when Codex needs to create a new personal plugin, add optional plugin structure, or generate or update marketplace entries for plugin ordering and availability metadata. - Skill: `pleaseai/plugin-creator` (Agent Skill, multi-file: 7 files) - Install (CLI): `npx skillmds@latest add pleaseai/plugin-creator` - Raw SKILL.md: https://api.skillmd.com/api/skills/pleaseai/plugin-creator/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: pleaseai (https://skillmd.com/u/pleaseai) - Updated: 2026-09-10 - Page: https://skillmd.com/skills/pleaseai/plugin-creator --- # Plugin Creator ## Quick Start 1. Run the scaffold script: ```bash # Plugin names are normalized to lower-case hyphen-case and must be <= 64 chars. # The generated folder and plugin.json name are always the same. # Run from repo root (or replace .agents/... with the absolute path to this SKILL). # By default creates in ~/plugins/. python3 .agents/skills/plugin-creator/scripts/create_basic_plugin.py ``` 2. Edit `/.codex-plugin/plugin.json` when the request gives specific metadata. The scaffold starts with valid defaults and must not contain `[TODO: ...]` placeholders. 3. Generate or update the personal marketplace entry when the plugin should appear in Codex UI ordering: ```bash # Personal marketplace entries default to ~/.agents/plugins/marketplace.json. python3 .agents/skills/plugin-creator/scripts/create_basic_plugin.py my-plugin --with-marketplace ``` Only use a repo/team marketplace when the user specifically asks for that destination: ```bash python3 .agents/skills/plugin-creator/scripts/create_basic_plugin.py my-plugin \ --path /plugins \ --marketplace-path /.agents/plugins/marketplace.json \ --with-marketplace ``` 4. Generate/adjust optional companion folders as needed: ```bash python3 .agents/skills/plugin-creator/scripts/create_basic_plugin.py my-plugin \ --path \ --marketplace-path \ --with-skills --with-hooks --with-scripts --with-assets --with-mcp --with-apps --with-marketplace ``` `` is the directory where the plugin folder `` will be created (for example `~/code/plugins`). 5. Before handing back a generated plugin, run: ```bash python3 .agents/skills/plugin-creator/scripts/validate_plugin.py ``` ## What this skill creates - Default marketplace-backed scaffolds are personal: `~/plugins//` plus `~/.agents/plugins/marketplace.json`. - Creates plugin root at `///`. - Always creates `///.codex-plugin/plugin.json`. - Fills the manifest with the validated schema shape that the ingestion path accepts. - Creates or updates `~/.agents/plugins/marketplace.json` when `--with-marketplace` is set. - If the marketplace file does not exist yet, seed a personal marketplace root before adding the first plugin entry. - `` is normalized using skill-creator naming rules: - `My Plugin` → `my-plugin` - `My--Plugin` → `my-plugin` - underscores, spaces, and punctuation are converted to `-` - result is lower-case hyphen-delimited with consecutive hyphens collapsed - Supports optional creation of: - `skills/` - `hooks/` - `scripts/` - `assets/` - `.mcp.json` - `.app.json` ## Marketplace workflow - Personal creation defaults to `~/.agents/plugins/marketplace.json`. - Repo/team marketplace creation is opt-in through both `--path` and `--marketplace-path`, only when the user specifically requests it. - In either location, the generated source path remains `./plugins/`. - Marketplace root metadata supports top-level `name` plus optional `interface.displayName`. - Treat plugin order in `plugins[]` as render order in Codex. Append new entries unless a user explicitly asks to reorder the list. - `displayName` belongs inside the marketplace `interface` object, not individual `plugins[]` entries. - Each generated marketplace entry must include all of: - `policy.installation` - `policy.authentication` - `category` - Default new entries to: - `policy.installation: "AVAILABLE"` - `policy.authentication: "ON_INSTALL"` - Override defaults only when the user explicitly specifies another allowed value. - Allowed `policy.installation` values: - `NOT_AVAILABLE` - `AVAILABLE` - `INSTALLED_BY_DEFAULT` - Allowed `policy.authentication` values: - `ON_INSTALL` - `ON_USE` - Treat `policy.products` as an override. Omit it unless the user explicitly requests product gating. - The generated plugin entry shape is: ```json { "name": "plugin-name", "source": { "source": "local", "path": "./plugins/plugin-name" }, "policy": { "installation": "AVAILABLE", "authentication": "ON_INSTALL" }, "category": "Productivity" } ``` - Use `--force` only when intentionally replacing an existing marketplace entry for the same plugin name. - If the target marketplace file does not exist yet, create it with top-level `"name"`, an `"interface"` object containing `"displayName"`, and a `plugins` array, then add the new entry. - For a brand-new marketplace file, the root object should look like: ```json { "name": "personal", "interface": { "displayName": "Personal" }, "plugins": [ { "name": "plugin-name", "source": { "source": "local", "path": "./plugins/plugin-name" }, "policy": { "installation": "AVAILABLE", "authentication": "ON_INSTALL" }, "category": "Productivity" } ] } ``` ## Required behavior - Outer folder name and `plugin.json` `"name"` are always the same normalized plugin name. - Do not remove required structure; keep `.codex-plugin/plugin.json` present. - Do not leave `[TODO: ...]` placeholders in plugin manifests. - Keep `apps` and `mcpServers` out of `plugin.json` unless their companion files are actually created. - Omit unsupported plugin manifest fields that validation rejects, including `hooks`. - If creating files inside an existing plugin path, use `--force` only when overwrite is intentional. - Preserve any existing marketplace `interface.displayName`. - When generating marketplace entries, always write `policy.installation`, `policy.authentication`, and `category` even if their values are defaults. - Add `policy.products` only when the user explicitly asks for that override. - Keep marketplace `source.path` relative to the selected marketplace root as `./plugins/`. - When the workflow created or updated a marketplace-backed plugin, end the final user-facing response with a short Codex app handoff. Say `To view this in the Codex app:` and write `View ` and `Share ` as Markdown links, not raw URLs or code spans. - The View deeplink uses `codex://plugins/?marketplacePath=`. The Share deeplink uses the same URL with `&mode=share`. - Replace the placeholders with the real normalized plugin name and absolute `marketplace.json` path from the scaffolded plugin. URL-encode the path segment and query value when needed. - Do not add `pluginName` or `hostId` query parameters to these deeplinks. Codex derives both after the user clicks the link. - Do not emit the `View ` or `Share ` links when no marketplace entry was created or updated. ## Reference to exact spec sample For the exact canonical sample JSON for both plugin manifests and marketplace entries, use: - `references/plugin-json-spec.md` ## Validation After editing `SKILL.md`, run: ```bash python3 /scripts/quick_validate.py .agents/skills/plugin-creator ``` Before handing back a generated plugin, run: ```bash python3 .agents/skills/plugin-creator/scripts/validate_plugin.py ```