Evaluate

/mcp-builder:evaluate

You are wrapping ${CLAUDE_PLUGIN_ROOT}/scripts/evaluation.py for the user. They have provided a QA XML file and a description of their MCP server. Your job: parse the description, build the right invocation, run it, and summarize the report.

Procedure

1. Verify prerequisites. Run these in parallel:

   • test -f "${CLAUDE_PLUGIN_ROOT}/scripts/evaluation.py" && echo OK (script exists)
   • python3 -c "import anthropic, mcp" 2>&1 (deps installed)
   • test -n "$ANTHROPIC_API_KEY" && echo OK || echo MISSING (API key set)

   If deps are missing, tell the user to run:

   pip install -r "${CLAUDE_PLUGIN_ROOT}/scripts/requirements.txt"
   

   If ANTHROPIC_API_KEY is unset, stop and ask the user to export it before retrying. Do not prompt them for the key value.

2. Parse the user's arguments. The first argument is the path to the eval XML file. Everything else describes the server. Map the description to transport flags:

   User says	Transport	Flags
   "stdio: node dist/index.js"	stdio	-t stdio -c node -a dist/index.js
   "stdio: python server.py with API_KEY=xyz"	stdio	-t stdio -c python -a server.py -e API_KEY=xyz
   "http://host/mcp" or "https://..."	http	-t http -u <url>
   "http://host/mcp with header Authorization: Bearer X"	http	-t http -u <url> -H "Authorization: Bearer X"
   "sse://..." or "SSE endpoint ..."	sse	-t sse -u <url>

   When the user's description is ambiguous, ask one targeted clarifying question rather than guessing.

3. Verify the eval file exists and preview it:

   test -f "<eval.xml>" && head -30 "<eval.xml>"
   

   If it's missing, stop and tell the user the path didn't resolve.

4. Run the evaluation. Allocate a tempfile with mktemp (so concurrent invocations don't clobber each other), then write the report there:

   REPORT=$(mktemp -t mcp-eval-report.XXXXXX.md)
   python3 "${CLAUDE_PLUGIN_ROOT}/scripts/evaluation.py" \
     <flags-from-step-2> \
     "<eval.xml>" \
     -o "$REPORT"
   echo "Report: $REPORT"
   

   Stream with a long timeout (evals take minutes). If the user passed -m <model> in their arguments, forward it; otherwise accept the script default.

5. Summarize the report. Read $REPORT and produce:

   • Accuracy (correct / total)
   • Average duration and tool calls per task
   • Names of any failed tasks and a one-line reason each (from their <feedback> block)
   • Path to the full report

   Do not paste the whole report — it's long. Offer to show specific failed tasks if the user asks.

Notes

• The harness is Python 3 and must find mcp + anthropic on the active interpreter. If the user's system has multiple Pythons, use python3 explicitly.
• For stdio transport, the harness launches the server itself — never start it separately first.
• For http/sse, the user must start their server before invoking this skill.
• Scoring is exact string match on <response> tags. A "failed" task may just mean the answer format differs — surface the actual vs. expected so the user can judge.

Source: make-heavy-metal/mcp-builder — distributed by TomeVault.