Python Patterns

Python Patterns — Team Conventions

Unified conventions for team Python projects: credential management, API clients, testing discipline, and data pipeline structure. Supplements standard patterns with team-specific rules.

When to Activate

• Writing credential/secret handling code or .env files
• Creating or modifying API clients (GitHub, Stripe, LLM APIs)
• Parsing LLM responses or structured API outputs
• Writing or reviewing tests (TDD workflow, mocking external APIs)
• Building or debugging data pipeline stages
• Reviewing code that handles HTTP responses or LLM output

Quick Rules

Credentials:

• Never hardcode or use real defaults. Fail fast if missing. Always create .env.example.

APIs:

• Always timeout (30s). Only retry transient errors (429, 5xx). Always validate response structure.

Tests:

• Mock external APIs. Set random_state=42. Target 80%+ coverage. Test behavior, not internals.

Pipelines:

• Each stage is independently runnable. Validate input before processing. Include metadata in every output. Fail fast on invalid data.

Details

Read references/credentials.md, references/api-clients.md, references/testing.md, and references/pipelines.md for full examples and anti-patterns.