Use a second session as the reviewer

Why it matters

The agent that did the work is the worst one to judge it. It remembers what it meant to do, not what it actually did.

Case had a separate reviewer and closer that checked the implementer’s work. Riker requires an independent reviewer before a job counts as done. A worker can never verify itself.

One warning from Riker: two models agreeing is not proof. A reviewer is good at catching things you didn’t mean. Your checks are still what prove the work is correct.

Exercise: review cold

1. Open a new Claude Code or Codex session, so it starts with none of the first session’s history.
2. Give it only your brief and the change (the diff, the branch, or the files).
3. Ask:

Here is the brief and the change. Don't fix anything.
List every way the change fails the brief, misses a "done when" line,
or changes something out of scope. Quote the exact lines.

Check yourself: for every finding, decide whether it’s real. Note which ones the first session’s summary didn’t mention.