I'll build an MCP client inspector that allows you to connect to MCP servers, inspect their tools, and test them interactively. This will be useful for debugging and exploring MCP servers.
I've built a comprehensive MCP client inspector that allows you to connect to and inspect Model Context Protocol servers 1. Here's what it includes:
Key Features
- Connection Management: Support for both SSE (HTTP) and stdio transports with configurable headers for authentication
- Tool Discovery: Lists all available tools from the connected MCP server with descriptions and parameter schemas
- Interactive Testing: Test tools with a dynamic form that adapts to each tool's parameter requirements
- Server Information: Display server capabilities and metadata
- Real-time Results: Execute tools and view formatted results
How to Use
- Connect: Choose your transport type (SSE for HTTP servers, stdio for local processes), enter the server URL, and optionally add authentication headers
- Explore Tools: Browse available tools, view their descriptions and required parameters
- Test Tools: Select a tool, fill in parameters, and execute it to see results
- Monitor: View server information and capabilities
The inspector includes mock API endpoints that simulate MCP server responses with sample tools like weather lookup, calculator, and dice rolling. In a real implementation, these would connect to actual MCP servers using the AI SDK's MCP client functionality 1.
I'll add Streamable HTTP transport support to the MCP client inspector, which is the newer transport method for HTTP-based MCP servers.
I've added Streamable HTTP transport support to the MCP client inspector! Here are the key improvements:
New Features
- Streamable HTTP Transport: Added support for the modern Streamable HTTP transport method 1, which is the recommended approach for production MCP servers
- Session Management: Includes session ID configuration for Streamable HTTP connections
- Real MCP Client Integration: Added actual AI SDK MCP client integration alongside the mock endpoints
- Transport Information: Added an info panel explaining the different transport types
- Fallback Support: Gracefully falls back to mock data if real MCP connection fails
Transport Options
- Streamable HTTP: Modern HTTP transport with session management (recommended)
- SSE: Server-Sent Events for real-time HTTP communication
- Stdio: Standard input/output for local CLI tools
How It Works
The inspector now attempts to create real MCP client connections using the AI SDK's experimental_createMCPClient function 1. For Streamable HTTP, it uses the StreamableHTTPClientTransport from the official MCP SDK, which provides better session management and reliability compared to basic SSE.
When you connect using Streamable HTTP:
- A session ID is generated or can be customized
- The client establishes a connection with proper session management
- Tools are discovered and can be executed through the real MCP protocol
- Results come directly from the actual MCP server
The inspector maintains backward compatibility with the mock endpoints for demonstration purposes when real connections aren't available.