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Give your agent tools with MCP (Python) · Challenge 05 · 中文版

Expose one real tool to your agent

Checkpoint l0510 ptsself-reported — code from verify.pyClaude Code 2.x (protocol: MCP 2026-07-28)

Wrap one function you actually own behind the validated, isolated boundary you just built.

Doing this with your agent? One sentence starts the whole course:

Read https://flypython.com/skills/flypython/SKILL.md and start the FlyPython course `mcp-server-in-python`.

Expose one real tool to your agent

Objective

Wrap one function you actually own behind the validated, isolated boundary you just built.

The lesson

Pick one read-only function from your own project — a lookup, a summary, a calculation. Register it as a tool with an explicit schema, reuse the validation and isolation patterns, and write its failure tests before wiring any client. The 2026-07-28 migration guide covers moving existing servers; this lesson is your first tool done right.

Exercise

  • Start with the failure tests; the schema is the contract
  • Record what you did not verify (client compliance, transport behavior)

Checkpoint

The lesson’s commands run, and you can answer these in your own words (the agent asks; you answer — that is the gate):

  1. Which command did this lesson run, and what did it decide?
  2. What failed at the start, and why — in your own words?
  3. Before trusting a similar change next time, what would you check first?

Expected evidence

The command transcript and your answers.

Hints

Stuck? Open one at a time.

Hint 1 — What this checkpoint tests

Exposing one real tool: wrap a function you own behind the validated, isolated boundary you just built.

Hint 2 — Schema honestly

Give the tool a real inputSchema naming required arguments — the boundary only earns trust if the schema tells the truth.

Hint 3 — The honest record

Note what your tool may and may not do — a schema that overclaims defeats the isolation you just proved.

Submit

Done? Record it.

The 8-character code verify.py progress printed for this checkpoint — from the browser, or straight from your agent.

Youbrowser

Submit the claim code

Your agentauto-submit

Let the agent solve and submit

Hand it this checkpoint (copy button on hover) — it solves, verifies, and submits on its own:

Work on the FlyPython challenge "Give your agent tools with MCP (Python)" (course id course-mcp-tools), checkpoint l05.
Machine-readable brief: https://flypython.com/api/challenges/mcp-server-in-python
Open the course folder and read TASK.md first — it is the contract.
Rules: smallest change, no new dependencies, never edit tests/ or solution/.
Check with python verify.py until its gates pass, then report each claim code to me.
Target: solve only checkpoint l05, and submit it as soon as it passes.

With a token from your agent page (env FLYPYTHON_TOKEN), it records the result directly:

curl -X POST https://flypython.com/api/claims \
  -H "Authorization: Bearer $FLYPYTHON_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"claims":[{"course":"mcp-server-in-python","checkpoint":"l05","code":"<8-char code>"}]}'

Or install the full FlyPython agent skill once and skip the paste.

Files

The starter and verifier

Solving runs on your machine — your agent fetches the course files itself via /api/challenges/mcp-server-in-python/files; you download nothing by hand. Prefer reading the source? Browse the folder on GitHub ↗