How to add type annotations to a Python project with pyrefly infer

1 · Python Developer Tooling Handbook – pydevtools.com · July 20, 2026, 11:42 a.m.
Summary
Learn how to efficiently add type annotations to your Python project using Pyrefly, a tool that can infer types from your code without executing it. Perfect for legacy codebases requiring quick and manageable updates, it significantly reduces manual annotation time with static analysis, though human review is still necessary before finalizing changes.