How to Test an MCP Server

Testing an MCP server is straightforward with MCP Playground. Follow these steps:

Enter the server URL - Paste the remote MCP server URL (e.g., https://mcp.example.com/sse)
Add authentication - If required, enter a Bearer token for protected servers
Connect - Click the connect button to establish a connection
Explore capabilities - Browse available tools, prompts, and resources
Test tools - Execute tools with custom parameters and see real-time responses

Need a server to test? Browse the MCP servers directory to find servers with remote URLs you can connect to.

What You Can Test

Tools: Execute server tools with custom arguments and view responses
Prompts: Retrieve and test prompt templates with variables
Resources: Access server resources like files, database records, or API data
Protocol Logs: View raw JSON-RPC messages for debugging
Connection Status: Monitor connection health and capabilities

Supported Transport Types

MCP Playground supports remote MCP servers using these transport protocols:

HTTP + SSE: Standard HTTP requests with Server-Sent Events for streaming responses
Streamable HTTP: Modern HTTP streaming for bidirectional communication

Note: STDIO-based servers require local installation and cannot be tested directly in the browser.

Frequently Asked Questions

Is MCP Playground free to use?

Yes! MCP Playground is completely free. Test MCP servers without any sign-up, credit card, or installation required. Just paste your MCP server URL and start testing.

Can I test local MCP servers?

MCP Playground works with remote MCP servers accessible via HTTP or SSE. For STDIO-based local servers, you'll need to use a local MCP client like Claude Desktop or Cursor IDE.

What MCP servers can I test?

You can test any MCP server with a remote URL. Popular options include Supabase MCP, GitHub MCP, Notion MCP, Playwright MCP, and many more. Browse our MCP servers list to find servers you can test.

Do I need to install anything?

No installation required! MCP Playground runs entirely in your browser. Just enter the MCP server URL, add authentication if needed, and click Connect.

How do I check if my MCP server is secure?

Use our free MCP server security scanner — paste your server URL and it runs 20+ checks covering HTTPS, authentication, TLS certificates, security headers, CORS policy, error verbosity, and rate limiting. No credentials required.

Check Your MCP Server Security

After testing your MCP server's functionality, the next step is verifying it's secure. Our free MCP security scanner runs 18 automated checks against your server URL — no credentials or installation required.

Authentication enforcement — checks whether unauthenticated requests are rejected
TLS certificate — validates HTTPS, cert expiry, and protocol version
tools/list exposure — detects if tool definitions are publicly accessible without auth
Security headers — HSTS, CORS, X-Frame-Options, Content-Security-Policy
Error verbosity — flags stack traces, file paths, or internal IPs in error responses
Rate limiting — tests whether the server throttles rapid requests

A February 2026 scan found over 8,000 MCP servers exposed on the public internet with no authentication. Check if your server is one of them.

Building Your Own MCP Server?

If you're developing an MCP server, use this tool to validate your implementation:

Verify tool schemas are correctly defined
Test tool execution and error handling
Debug protocol-level issues with the log viewer
Validate authentication flows

Learn more in our guide on building a custom MCP server.