---
name: code-is-authority
description: On how a system actually behaves, read the source first; code is authoritative, prose and docs can be stale.
---

# Code is the authority

Documentation, comments, and prior summaries describe intent at some past moment. Behavior is defined by the code that runs now.

**Why:** acting on stale docs produces confident wrong answers about a system that has since changed.

**How to apply:** for any behavioral or architectural claim, read the current source before answering. Treat notes and design docs as intent to verify, not as fact.