Runnable examples
Run the check yourself. Then let an agent try.
Each example ships a task contract, a deliberately broken starter, a verified solution, and a one-command verifier. Reproduce the failure first, hand the contract to your coding agent, and verify the result locally — no account, no API key, no trust required.
All runnable examples
MCP tool server (2026-07-28 specification)
Build a stateless MCP tool server with JSON-RPC 2.0 dispatch, schema validation, error isolation, and the input_required round-trip — with no initialize handshake.
02Async batch fetcher with bounded concurrency
Implement a resilient async batcher with Semaphore concurrency control, exponential backoff for transient failures, and per-item error isolation.
03Validate untrusted boundary payloads
Parse, sanitize, and validate messy external payloads with field normalization and structured error contracts.
04Resilient batch data pipeline
Build an isolated, bounded data batch processing pipeline with error recovery using the standard library.
05Three-minute AI-coding change
Reproduce a Python text-boundary bug, make a bounded fix, and verify it with the standard library.
One repository
Clone, verify, and hand the contract to your agent.
Every example lives in the open FlyPython repository and runs with the Python standard library alone. Reviewed dates and checksums for each document are published in the repository content manifest.
git clone https://github.com/flypythoncom/python.git
cd python && python examples/mcp-server/verify.py solution