Independent review — the cross-model gate

A blocking review gate. Its value is independence: a model that did not write the artifact, ideally from another model family, does not share the author's blind spots. This file holds the working rules. Why they exist, the incidents behind them and the long form of each test are in references/rationale.md — read the matching section when a rule's application is contested.

• PLAN gate — a planning markdown, before any code is written.
• DIFF gate — a branch/PR diff, before merge.

Gate on consequence, not size. A docs row whose "suggested fix" someone will implement, a runbook headed for production, or a plan an agent will execute weighs more than a small code change CI will catch. Pick the depth by that (Review depth, below), name it and why in the trail; never skip silently. With a config diff, send the code that reads the config too.