4 Best Claude Prompts for Code Documentation (2026)

Here is my project: [PASTE package.json/pyproject + entry file + one core module].

Write a README that answers, in order: what this does (2 sentences, no adjectives), who it's for, the 5-minute quickstart (commands that actually run), the 3 most common tasks with examples, and honest limitations. Ban the phrases "blazingly fast", "simple yet powerful", and any badge wall. If you can't determine something from the code, write TODO(owner) instead of inventing it.

Generate reference documentation for these public functions/endpoints:
[PASTE CODE OR OPENAPI SPEC]

For each: signature, plain-English one-liner, parameters with types AND valid ranges, return shape with a realistic example, every error it can raise and when, and one non-obvious usage note. Order by how often a user will need them, not alphabetically.

Based on this codebase structure: [PASTE DIRECTORY TREE + KEY FILES], write an architecture overview for engineers: the 4-6 major components and their responsibilities, how a request/data flows through them (as a numbered trace), the 3 most important design decisions you can infer WITH their likely rationale, and where the bodies are buried — the parts that will confuse newcomers.

Turn the above into a day-one onboarding doc: environment setup (exact commands), 'make your first change' walkthrough targeting a genuinely easy file, the 5 questions newcomers always ask (answered), and a self-test: 3 tasks a newcomer should be able to do after reading — with the answers hidden at the bottom. Flag any setup step you suspect is broken or undocumented.