FastMCP CLI: List and Call Use fastmcp list and fastmcp call to interact with any MCP server from the command line. Listing Tools

Remote server

fastmcp list http://localhost:8000/mcp

Local Python file (runs via fastmcp run automatically)

fastmcp list server.py

MCPConfig with multiple servers

fastmcp list mcp.json

Stdio command (npx, uvx, etc.)

fastmcp list --command 'npx -y @modelcontextprotocol/server-github'

Include full input/output schemas

fastmcp list server.py --input-schema --output-schema

Machine-readable JSON

fastmcp list server.py --json

Include resources and prompts

fastmcp list server.py --resources --prompts Default output shows tool signatures and descriptions. Use --input-schema or --output-schema to include full JSON schemas, --json for structured output. Calling Tools

Key=value arguments (auto-coerced to correct types)

fastmcp call server.py greet name = World fastmcp call server.py add a = 3 b = 4

Single JSON object for complex/nested args

fastmcp call server.py create_item '{"name": "Widget", "tags": ["a", "b"]}'

--input-json with key=value overrides

fastmcp call server.py search --input-json '{"query": "hello", "limit": 5}' limit = 10

JSON output for scripting

fastmcp call server.py add a = 3 b = 4 --json Type coercion is automatic: limit=5 becomes an integer, verbose=true becomes a boolean, based on the tool's input schema. Server Targets All commands accept the same server targets: Target Example HTTP/HTTPS URL http://localhost:8000/mcp Python file server.py MCPConfig JSON mcp.json (must have mcpServers key) Stdio command --command 'npx -y @mcp/server' Discovered name weather or source:name Servers configured in editor configs (Claude Desktop, Claude Code, Cursor, Gemini CLI, Goose) or project-level mcp.json can be referenced by name. Use source:name (e.g. claude-code:my-server , cursor:weather ) to target a specific source. Run fastmcp discover to see available names. For SSE servers, pass --transport sse : fastmcp list http://localhost:8000/mcp --transport sse Auth HTTP targets automatically use OAuth (no-ops if the server doesn't require auth). Disable with --auth none : fastmcp call http://server/mcp tool --auth none Discovering Configured Servers

See all MCP servers in editor/project configs

fastmcp discover

Filter by source

fastmcp discover --source claude-code

JSON output

fastmcp discover --json Scans Claude Desktop, Claude Code, Cursor, Gemini CLI, Goose, and ./mcp.json . Sources: claude-desktop , claude-code , cursor , gemini , goose , project . Workflow Pattern Discover tools first, then call them:

1. See what servers are configured