microsoft / mcp-inspector-testing
Validate Wassette changes end-to-end by running the MCP server with just and driving it with the MCP Inspector CLI over Streamable HTTP — listing tools, resources, and prompts, and calling tools. Use before committing server changes or when debugging tool exposure and behavior.
0
SKILL.md2.9 KB
mcp-inspector-testing skill
Test server-facing Wassette changes with the MCP Inspector before committing.
This confirms the server starts, tools are exposed over MCP, tool calls behave
as expected, and no regressions slipped in.
Workflow
- Build your changes:
just build. Start the server (Terminal 1):
just run, or an example such asjust run-fetch-rs. The server listens at127.0.0.1:9001/mcpover
Streamable HTTP.- Drive it with the Inspector (Terminal 2) — always run
tools/listfirst. - Capture Inspector output when it helps demonstrate or debug the change.
Running the server
just run # Default server
just run RUST_LOG='debug' # Verbose logs
just run-filesystem # Example: filesystem component
just run-fetch-rs # Example: fetch component
just run-memory # Example: memory component
just run-get-weather # Example: weather (needs OPENWEATHER_API_KEY)Inspecting with the MCP Inspector
BASE=http://127.0.0.1:9001/mcp
# List capabilities (run tools/list first)
npx @modelcontextprotocol/inspector --cli $BASE --transport http --method tools/list
npx @modelcontextprotocol/inspector --cli $BASE --transport http --method resources/list
npx @modelcontextprotocol/inspector --cli $BASE --transport http --method prompts/list
# Call a tool
npx @modelcontextprotocol/inspector --cli $BASE --transport http \
--method tools/call --tool-name mytool --tool-arg key=value
# Multiple args, or JSON for complex parameters
npx @modelcontextprotocol/inspector --cli $BASE --transport http \
--method tools/call --tool-name mytool --tool-arg key1=v1 --tool-arg key2=v2
npx @modelcontextprotocol/inspector --cli $BASE --transport http \
--method tools/call --tool-name mytool --tool-arg 'options={"format":"json","max_tokens":100}'
# Custom headers (e.g. auth testing)
npx @modelcontextprotocol/inspector --cli $BASE --transport http \
--method tools/list --header "X-API-Key: your-api-key"Capturing output
npx @modelcontextprotocol/inspector --cli $BASE --transport http \
--method tools/list > inspector-output.txtInclude captured output in review notes or issue comments when it helps
demonstrate a fix.
Troubleshooting
- Confirm
just runstarted without errors. - Run
tools/listto see what is actually exposed. - Re-run the server with
RUST_LOG=debugfor detailed logs. - Start with simple tool calls, then add argument complexity.
- Compare against a known-good example such as
fetch-rs.