Python Automation Skill

This skill provides concrete Python patterns to implement robust REST API automations.

When to use this skill

• •Python scripts that call one or more REST APIs
• •ETL jobs, sync tools, webhook handlers
• •CLI tools or small services that integrate external systems

Preferred stack (defaults)

• •HTTP client: httpx (preferred) or requests
• •Config: env vars + .env (optional) with pydantic-settings if appropriate
• •Logging: stdlib logging with structured-ish fields
• •Testing: pytest (+ respx for httpx mocking when useful)

If the project already uses different tools, follow project conventions.

Reference architecture (small but scalable)

• •client.py: API client wrapper (auth headers, retries, pagination helpers)
• •models.py: typed payload models (dataclasses or pydantic)
• •sync.py: orchestration logic (fetch -> transform -> upsert)
• •main.py: CLI entrypoint
• •tests/: unit tests for transform + client behavior

HTTP rules (mandatory)

• •Always set timeouts (connect + read)
• •Centralize request sending in one function so retries/logging are consistent
• •Never log secrets (Authorization headers, tokens)

Retry policy guidance

Retry on:

• •network errors/timeouts
• •429 (respect Retry-After when present)
• •500–599 Optional: 408, and 409 only if operation is safe and semantics known

Do NOT retry on:

• •most 400–499 (unless explicitly safe)

Timeouts

• •Set explicit timeouts; do not rely on defaults.
• •Use smaller connect timeout; moderate read timeout.

Pagination patterns

Support at least one helper that can handle:

• •next URL in response
• •cursor token in response
• •page/limit parameters

Add a hard stop:

• •max pages OR max items OR max elapsed time

Idempotency patterns (Python)

Choose and document:

• •Use an Idempotency-Key header when supported
• •Upsert using a stable external_id
• •Persist a lightweight state store:
  • •simplest: SQLite file (recommended for OSS)
  • •alternative: JSONL log + compaction

Minimum: ensure repeated runs don’t create duplicates.

Observability (Python)

Minimum logs should include:

• •run_id
• •request: method, url/path, status_code, elapsed_ms, attempt
• •record counts: processed/created/updated/skipped/failed

Also include a final summary log line.

Verification requirements

For non-trivial work, add:

• •unit tests for mapping/transform logic
• •at least one test for pagination or retry behavior (mocked)
• •a “dry-run” CLI flag (prints intended writes)

Output format when writing code

• •Provide a small directory layout
• •Explain how to configure env vars
• •Include exact commands to run (and test)