Inspecting Servers

import { VersionBadge } from '/snippets/version-badge.mdx'

fastmcp inspect loads a server and reports what it contains — its tools, resources, prompts, version, and metadata. The default output is a human-readable summary:

fastmcp inspect server.py

Server: MyServer
Instructions: A helpful MCP server
Version: 1.0.0

Components:
  Tools: 5
  Prompts: 2
  Resources: 3
  Templates: 1

Environment:
  FastMCP: 2.0.0
  MCP: 1.0.0

Use --format [fastmcp|mcp] for complete JSON output

JSON Output

For programmatic use, two JSON formats are available:

FastMCP format (--format fastmcp) includes everything FastMCP knows about the server — tool tags, enabled status, output schemas, annotations, and custom metadata. Field names use snake_case. This is the format for debugging and introspecting FastMCP servers.

MCP protocol format (--format mcp) shows exactly what MCP clients see through the protocol — only standard MCP fields, camelCase names, no FastMCP-specific extensions. This is the format for verifying client compatibility and debugging what clients actually receive.

# Full FastMCP metadata to stdout
fastmcp inspect server.py --format fastmcp

# MCP protocol view saved to file
fastmcp inspect server.py --format mcp -o manifest.json

Options

Entrypoints

The inspect command supports the same local entrypoints as fastmcp run: inferred instances, explicit entrypoints, factory functions, and fastmcp.json configs.

fastmcp inspect server.py                  # inferred instance
fastmcp inspect server.py:my_server        # explicit entrypoint
fastmcp inspect server.py:create_server    # factory function
fastmcp inspect fastmcp.json               # config file