deckard-mcp

MCP server that exposes the deckard plugin manager as MCP tools. Built on FastMCP 3.x.

Overview

deckard-mcp wraps the deckard Python library directly — no subprocess or CLI invocation. Read operations (list, search, info) execute immediately. Write operations (install, remove, marketplace changes) always trigger an elicitation confirmation before doing anything.

Installation

# Install deckard first (from the sibling directory)
pip install -e ../deckard

# Install deckard-mcp
pip install -e .

Usage

Run in stdio mode (default):

deckard-mcp

Run in HTTP mode:

PORT=8080 deckard-mcp

Tools

Read-only (no confirmation required)

Tool	Description
list_plugins	List all installed plugins. Accepts scope (all/global/project/local) and optional project_root.
list_marketplaces	List all known marketplaces (official + user-defined from ~/.claude/settings.json).
search_plugins	Search marketplace catalogs by query. Optional marketplace and category filters.
get_plugin_info	Fetch full details for a plugin. Supports name@marketplace syntax.

Write (elicitation confirmation required)

Tool	Description
install_plugin_tool	Install a plugin from the marketplace or a local path. Supports scope, providers, and overwrite.
remove_plugin_tool	Remove an installed plugin and update settings.json.
add_marketplace	Add a custom marketplace to ~/.claude/settings.json extraKnownMarketplaces.
remove_marketplace	Remove a custom marketplace from settings. The official claude-plugins marketplace is protected.

Provider deployment

Both install_plugin_tool and remove_plugin_tool accept a providers parameter to sync the plugin across additional tool providers after the Claude Code cache is updated. Accepts a comma-separated list or all.

Valid providers: cursor, codex, opencode, copilot, roocode

MCP host configuration

Add to your MCP host config (e.g. ~/.claude/claude_desktop_config.json):

{
  "mcpServers": {
    "deckard": {
      "command": "deckard-mcp"
    }
  }
}

Or with uvx if installed via uv:

{
  "mcpServers": {
    "deckard": {
      "command": "uvx",
      "args": ["--from", "/path/to/deckard-mcp", "deckard-mcp"]
    }
  }
}