MCP CLI

A command-line interface for interacting with the MCP Registry Service and connecting directly to MCP servers.

Features

• Registry Service Integration:

  • List registered MCP servers
  • Get detailed server information by ID or name
  • Check service health and status
  • Service ping functionality
  • Pagination support for listing servers
  • Pattern matching for server searches

• Direct MCP Server Connection:

  • Connect to MCP servers via stdio transport
  • Connect to HTTP-based MCP servers
  • Interactive mode for real-time server exploration
  • Tool execution with argument parsing
  • Resource reading capabilities
  • Prompt listing and interaction

Installation

Clone the repository and build using Make:

git clone https://github.com/jbovet/mcp-cli.git
cd mcp-cli
make build

The binary will be created in bin/mcp-cli.

Usage

Registry Service Commands

# List all servers
mcp-cli get servers

# Get server details by ID
mcp-cli get server 123e4567-e89b-12d3-a456-426614174000

# Get server details by name
mcp-cli get server io.github.owner/server-name

# Search servers by name pattern
mcp-cli get server redis --name --show-matches

# Check service health
mcp-cli health

# Ping service
mcp-cli ping

Direct MCP Server Connection

Stdio Transport (Local Processes)

# Connect to a Python MCP server
mcp-cli connect --type stdio --command "python" --args "server.py"

# Connect to a Node.js MCP server with environment variables
mcp-cli connect --type stdio --command "node" --args "server.js" --env "DEBUG=1"

# Connect using command string parsing
mcp-cli connect --type stdio --command "python /path/to/server.py --port 8080"

# Interactive mode for exploration
mcp-cli connect --type stdio --command "python server.py" --interactive

HTTP Transport (Remote Servers)

# Connect to HTTP MCP server
mcp-cli connect --type http --url "http://localhost:8080/mcp"

# Connect to HTTPS MCP server
mcp-cli connect --type streamable --url "https://api.example.com/mcp"

# Interactive mode with HTTP server
mcp-cli connect --type http --url "http://localhost:8080/mcp" --interactive

Interactive Mode Commands

When running with --interactive, you can use these commands:

# List server capabilities
tools         # List available tools
resources     # List available resources  
prompts       # List available prompts

# Execute operations
call <tool-name> [args...]    # Call a tool with arguments
read <resource-uri>           # Read a resource by URI

# Navigation
help          # Show help message
quit/exit     # Exit interactive mode

Example Interactive Session

> tools
Available tools (3):
1. validate_api - Validate API specifications
2. format_code - Format source code
3. analyze_logs - Analyze log files

> call validate_api openapi.yaml
Tool 'validate_api' result:
✅ Tool executed successfully:
    API specification is valid
    Found 12 endpoints
    No validation errors

> resources
Available resources (2):
1. file://config.json (Configuration) - Server configuration
2. file://schema.yaml (Schema) - API schema definition

> read file://config.json
Resource content:
  Text (application/json): {"server": {"port": 8080}}

> quit
Goodbye!

Global Flags

• --url: Base URL of the MCP Registry Service (default: http://localhost:8080)
• --verbose, -v: Enable verbose output

Registry Service Options

• --limit: Maximum number of servers to return (1-100)
• --cursor: Pagination cursor for fetching next page

Connect Command Options

• --type: Transport type (stdio, http, streamable)
• --url: Server URL for HTTP-based connections
• --command: Command to execute for stdio connections
• --args: Arguments for the command (can be repeated)
• --env: Environment variables for the command (can be repeated)
• --timeout: Connection timeout (default: 60s)
• --interactive: Run in interactive mode

Development

Requirements

• Go 1.24.3 or later
• Make

Common Tasks

# Install dependencies
make deps

# Run tests
make test

# Format code
make fmt

# Run linter
make lint

# Clean build artifacts
make clean

Project Structure

cmd/        - Command implementations
  connect.go      - MCP server connection command
  get.go         - Registry "get" command group
  server.go      - Individual server details
  servers.go     - Server listing
  health.go      - Health check command
  ping.go        - Ping command
pkg/        - Core packages
  client/   - Registry API client implementation
  models/   - Data models
  adapter/  - MCP server adapters (stdio, HTTP)
    adapter.go    - Core adapter interfaces
    stdio.go      - Stdio transport implementation
    http.go       - HTTP transport implementation
    factory.go    - Adapter factory and utilities
bin/        - Build output

Use Cases

Registry Integration

• Discover available MCP servers in the registry
• Get detailed information about server capabilities
• Monitor registry service health

Direct Server Testing

• Test MCP server implementations during development
• Validate tool and resource functionality
• Interactive debugging and exploration
• Automated testing and validation scripts

CI/CD Integration

• Health checks in deployment pipelines
• Automated server capability validation
• Registry service monitoring

License

MIT License - see LICENSE.md for details.