Marketplace Format Specification

A marketplace is a Git repository that indexes babysitter plugins via a marketplace.json manifest. The babysitter SDK clones these repositories locally and reads the manifest to discover available plugins.

marketplace.json Schema

The root manifest file must be named marketplace.json and placed at the repository root.

Top-Level Fields

Field	Type	Required	Description
name	string	Yes	Human-readable marketplace name. This becomes the directory name when cloned locally.
description	string	Yes	Short description of the marketplace
url	string	Yes	Git remote URL of the marketplace repository
owner	string	Yes	Marketplace owner name or organization
plugins	object	Yes	Map of plugin name to MarketplacePluginEntry

MarketplacePluginEntry Fields

Each key in the plugins object is the plugin name (e.g., "babysitter@a5c.ai"), and each value has the following structure:

Field	Type	Required	Description
name	string	Yes	Human-readable plugin name (should match the key)
description	string	Yes	Short description of the plugin
latestVersion	string	Yes	Latest available semantic version
versions	string[]	Yes	List of all available versions, newest first
packagePath	string	Yes	Relative path to the plugin package directory within the marketplace repository
tags	string[]	Yes	Searchable tags for categorization
author	string	Yes	Plugin author name or identifier

Example marketplace.json

{
  "name": "babysitter-marketplace",
  "description": "Official marketplace for babysitter plugins",
  "url": "https://github.com/a5c-ai/babysitter-marketplace.git",
  "owner": "a5c-ai",
  "plugins": {
    "babysitter@a5c.ai": {
      "name": "babysitter@a5c.ai",
      "description": "Core babysitter plugin for AI-assisted development workflows",
      "latestVersion": "0.0.176",
      "versions": ["0.0.176", "0.0.175", "0.0.174"],
      "packagePath": "plugins/babysitter-unified",
      "tags": ["core", "development", "ai"],
      "author": "a5c-ai"
    },
    "code-review@a5c.ai": {
      "name": "code-review@a5c.ai",
      "description": "Automated code review plugin",
      "latestVersion": "1.2.0",
      "versions": ["1.2.0", "1.1.0", "1.0.0"],
      "packagePath": "plugins/code-review",
      "tags": ["review", "quality"],
      "author": "a5c-ai"
    }
  }
}

Repository Directory Structure

A marketplace repository should follow this layout:

babysitter-marketplace/
  marketplace.json            # Manifest (required)
  plugins/
    babysitter-unified/       # Plugin package directory
      install.md
      uninstall.md
      configure.md
      install-process.js
      migrations/
        0.0.174_to_0.0.175.md
        0.0.175_to_0.0.176.md
    code-review/
      install.md
      uninstall.md
      configure.md
      migrations/
        1.0.0_to_1.1.0.md
        1.1.0_to_1.2.0.md

The packagePath field in each plugin entry points to the relative path within the repository or marketplace checkout (for example, "plugins/babysitter-unified" in this repo).

Local Clone Structure

When a marketplace is cloned via plugin:add-marketplace, it is stored under the babysitter configuration directory:

• Global scope: ~/.babysitter/marketplaces/<marketplace-name>/
• Project scope: <projectDir>/.babysitter/marketplaces/<marketplace-name>/

The marketplace name is derived from the Git URL (the repository name without the .git suffix). For example, cloning https://github.com/a5c-ai/babysitter-marketplace.git produces a directory named babysitter-marketplace.

Version Tracking

The latestVersion field in each plugin entry determines the default version used during plugin:install when no --plugin-version flag is provided. The versions array provides a complete history for reference, listed newest first.

Version strings follow semantic versioning conventions (e.g., 1.0.0, 2.0.0-beta.1). Pre-release identifiers with dashes and dots are supported.

Creating a Marketplace Repository

1. Create a new Git repository.

2. Create a marketplace.json at the root with the schema described above.

3. Create plugin package directories under a conventional path (typically plugins/).

4. For each plugin, add an entry to marketplace.json with the packagePath pointing to the plugin package directory.

5. Push the repository to a Git remote (GitHub, GitLab, Bitbucket, or any Git-accessible URL).

6. Users can then add the marketplace:

   babysitter plugin:add-marketplace --marketplace-url <your-repo-url> --global

Updating the Marketplace

When you release a new plugin version:

1. Update the plugin package directory with new instruction files and migration files.
2. Update the latestVersion field in marketplace.json.
3. Add the new version to the front of the versions array.
4. Commit and push the changes.

Users update their local clone with:

babysitter plugin:update-marketplace --marketplace-name <name> --global

TypeScript Interfaces

The marketplace types are defined in packages/sdk/src/plugins/types.ts:

• MarketplaceManifest -- The full manifest structure
• MarketplacePluginEntry -- A single plugin entry within the manifest
• MARKETPLACE_MANIFEST_FILENAME -- The constant "marketplace.json"