prefecthq--fastmcp/examples/skills

Skills Provider Example

This example demonstrates how to expose agent skills (like Claude Code skills) as MCP resources.

Structure

skills/
├── README.md              # This file
├── server.py              # MCP server that exposes skills
├── client.py              # Example client that discovers and reads skills
└── sample_skills/         # Example skills directory
    ├── pdf-processing/
    │   ├── SKILL.md       # Main skill file
    │   └── reference.md   # Supporting documentation
    └── code-review/
        └── SKILL.md       # Main skill file

Running the Example

1. Start the server:

   uv run python examples/skills/server.py
   

2. In another terminal, run the client:

   uv run python examples/skills/client.py
   

How It Works

The skills provider system has a two-layer architecture:

• SkillProvider - Handles a single skill folder, exposing its files as resources
• SkillsDirectoryProvider - Scans a directory, creates a SkillProvider per folder
• ClaudeSkillsProvider - Convenience subclass for Claude Code skills (~/.claude/skills/)

For each skill, the provider exposes:

• A Resource for the main file (skill://{name}/SKILL.md)
• A Resource for a synthetic manifest (skill://{name}/_manifest)
• Supporting files via ResourceTemplate or Resources (configurable)

Progressive Disclosure

When a client lists resources, they see skill names and descriptions (from frontmatter) without fetching the full content. This keeps the discovery cost low.

By default, supporting files are exposed via ResourceTemplate (hidden from list_resources()). Set supporting_files="resources" to make them visible:

SkillsDirectoryProvider(roots=skills_dir, supporting_files="resources")

The Manifest

The _manifest resource provides a JSON listing of all files in a skill:

{
  "skill": "pdf-processing",
  "files": [
    {"path": "SKILL.md", "size": 1234, "hash": "sha256:abc..."},
    {"path": "reference.md", "size": 5678, "hash": "sha256:def..."}
  ]
}

This enables clients to download entire skills for local use.

Usage Examples

Single Skill

from pathlib import Path
from fastmcp import FastMCP
from fastmcp.server.providers.skills import SkillProvider

mcp = FastMCP("My Skill")
mcp.add_provider(SkillProvider(Path.home() / ".claude/skills/pdf-processing"))
mcp.run()

All Skills in a Directory

from fastmcp.server.providers.skills import SkillsDirectoryProvider

mcp = FastMCP("Skills")
mcp.add_provider(SkillsDirectoryProvider(roots=Path.home() / ".claude" / "skills"))
mcp.run()

Claude Code Skills (default location)

from fastmcp import FastMCP
from fastmcp.server.providers.skills import ClaudeSkillsProvider

mcp = FastMCP("My Skills")
mcp.add_provider(ClaudeSkillsProvider())  # Uses ~/.claude/skills/
mcp.run()