mcpbin

MCP testing server built with FastMCP. Provides tools, resources, and prompts for testing MCP client implementations.

Installation

uv sync

Usage

Claude Code

Add the hosted mcpbin server to Claude Code:

claude mcp add --scope local --transport http mcpbin https://mcpbin.fastmcp.app/mcp

Local Development

make dev

Tools

Echo & Context

• echo - Echo back input data
• echo_context - Return request context info

Errors

• status_error - Raise error with message/code
• random_error - Random success/failure

Timing

• delay - Wait for specified duration

Data

• generate_uuid - Generate UUID v4
• timestamp - Get current timestamp
• base64_encode / base64_decode - Base64 encoding

Sampling

• sample_echo - Basic LLM sampling
• sample_with_system - Sampling with system prompt
• sample_with_params - Sampling with temperature/max_tokens
• sample_multi_turn - Multi-turn conversation

Elicitations

• elicit_string - Request string input
• elicit_number - Request integer input
• elicit_boolean - Request boolean input
• elicit_choice - Request choice from options
• elicit_structured - Request structured data

Resources

• resource://echo/{message} - Echo message
• resource://bytes/{size} - Random bytes
• resource://json/sample - Sample JSON data

Development

make test    # Run tests
make lint    # Check code style
make format  # Format code