Avoid Types Based on Anecdotal Data

Overview

Don't infer types from a single example.

If you create a type based on one API response or one sample, you'll miss edge cases. Get authoritative type definitions or examine multiple examples to understand the full shape of your data.

When to Use This Skill

• Creating types for external APIs
• Typing data from databases
• Working with third-party services
• Debugging "impossible" type errors

The Iron Rule