What is MCP Inspector?
The MCP Inspector is a free, browser-based developer utility designed to test and debug Model Context Protocol (MCP) servers. Built by Anthropic, the Model Context Protocol is an open standard that enables AI models (like Claude) to safely and securely connect to external tools, databases, and local data.
Developers building custom MCP integrations need a simple, reliable environment to verify that their schemas, endpoints, and authentication flows conform to specification before deploying them to live models. This tool mimics a stateful MCP client directly inside your browser using raw transport mechanisms, allowing you to debug live environments instantly without writing any bootstrap code.
Features
✓ Test via HTTP/SSE
Connect securely to any compliant endpoint using standard SSE transport stream channels.
✓ 2025-06-18 Spec Support
Strictly compliant with the latest version of the Model Context Protocol, including structured content payloads.
✓ Dynamic Parameter Forms
Dynamic form rendering inspects tool schemas on-the-fly and creates native HTML validated inputs.
✓ Browse Resources & Prompts
Directly view and inspect the catalog of available data nodes, configurations, and templates.
✓ Accept Server Elicitations
Fully integrated handler frameworks allowing servers to request contextual input securely from users.
✓ No Signups or Installs
100% free and open-source tool. Runs immediately in your browser, keeping operations completely offline if needed.
How to Use
- 1
Enter your MCP Server URL
Type in your locally hosted or public MCP endpoint (supporting HTTP/SSE) in the server URL field above.
- 2
Click Connect
The inspector initiates handshakes and initializes stateful sessions complying with standard protocol handshakes.
- 3
Browse Capabilities
Browse through the available categories inside the interactive tabs (Tools, Resources, Prompts, Elicitations).
- 4
Execute and Debug
Select any tool, fill out the dynamically generated parameters schema, and click 'Test Tool' to run it.
- 5
Inspect Raw Output
Review visual base64 images, parsed texts, and the underlying JSON payload traces inside the Response Viewer.
Popular MCP Servers to Test
Filesystem MCP
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Memory MCP
A knowledge graph server storing stateful facts, concepts, and episodic history across distinct chat sessions for persistent memory.
GitHub MCP
Exposes pull requests, repositories, issue tracking systems, and code reviews directly to your AI agents for contextual workflow automation.
Custom APIs
Build custom integrations for proprietary internal databases, search utilities, or tools utilizing the standard SDK specifications.
What is Model Context Protocol?
The Model Context Protocol (MCP) is a standardized open-source protocol built to solve the fragmentation of AI tool integrations. Much like how USB standardized device connectivity for hardware, MCP aims to create a universal channel between Large Language Models (LLMs) and various data sources or operations.
By defining a uniform contract, LLMs can contextually query, read, and invoke code platforms without rewriting unique interface bridges for every new application. The latest 2025-06-18 specification updates bring major structural enhancements, including support for custom structured content schemas, simplified state initialization headers, robust elicitation request flows, and improved error serialization.