MCP Server Testing Suite

This skill provides two testing modes for MCP servers, both powered by @mcp-use/inspector .

How it works

The inspector runs a local web server that proxies JSON-RPC requests to your MCP server. Every MCP operation (initialize, tools/list, tools/call, resources/list, prompts/get, etc.) goes through curl calls to the inspector's API. This means you can test any MCP server reachable over HTTP/SSE or WebSocket without needing a config file or daemon.

Command: /mcp-test

Basic protocol-level testing. Verifies every MCP primitive works correctly.

When the user invokes /mcp-test , follow the guide in references/basic-test-guide.md . This command:

• Asks the user for their MCP server URL (or detects it from context)

• Starts the inspector in the background

• Runs through every MCP primitive systematically

• Reports pass/fail for each check

• Cleans up the inspector process

Read references/basic-test-guide.md for the complete step-by-step procedure.

Command: /mcp-test-llm

End-to-end LLM-powered testing. Uses a real LLM to generate business-relevant test scenarios and execute them against the MCP server with tool-use.

When the user invokes /mcp-test-llm , follow the guide in references/llm-test-guide.md . This command:

• Asks the user for their MCP server URL

• Asks for an LLM API key (OpenAI, Anthropic, Google, or OpenRouter)

• Optionally saves credentials to .env

• Discovers all tools and their schemas

• Generates business-relevant test cases based on what the tools actually do

• Executes each test case through the LLM chat endpoint

• Validates tool calls were made and results are sensible

• Reports comprehensive results

Read references/llm-test-guide.md for the complete step-by-step procedure. Read references/providers.md for LLM provider configuration details (including OpenRouter).

Reference files

File When to read

references/basic-test-guide.md

When running /mcp-test

references/llm-test-guide.md

When running /mcp-test-llm

references/inspector-api.md

Full API reference for the inspector (both commands use this)

references/providers.md

LLM provider setup including OpenRouter, base URL overrides

references/troubleshooting.md

When something fails and you need to debug

references/business-cases.md

How to generate realistic business test cases from tool schemas

Important conventions

• Always use --no-open when starting the inspector (agents don't need browsers)

• Always disable telemetry: MCP_USE_ANONYMIZED_TELEMETRY=false

• Always clean up the inspector process when done (kill $INSPECTOR_PID )

• Use the crash thinking tool to structure your reasoning at each testing phase

• Report results as a clear pass/fail table, not walls of JSON

• If a test fails, dig into why before moving on — read error messages, check schemas, retry with different inputs