Five arrangements all get called open source AI code review. The license badge does not tell you which one you have. What to check in the repo, the license file, and the vendor's own README.
Approval invalidation is a repository setting, and an agent's fix loop hits it on every push. What GitHub, GitLab, CodeRabbit and Kodus document about re-review rounds.
Per-review file caps and per-developer refill rates decide whether an AI reviewer keeps up with agent output. What CodeRabbit, Copilot and Kodus document, and which limit binds first.
Free means four different arrangements in AI code review. What CodeRabbit, Greptile, Qodo, Copilot and Kodus include on a free tier, and the metering unit that decides whether you get a review or a demo.
Once pull requests outnumber review hours, a ranking layer decides what gets read. CodeRabbit Triage, Kodus Cockpit and GitHub's own metrics each document what their numbers leave out.
A bot review only blocks or clears a merge if the repository says so. What Copilot, CodeRabbit, Kodus and Graphite document, and the effort dial behind it.
Required approvals are a paid GitLab feature. What CodeRabbit, Qodo, GitLab Duo, Copilot and Kodus each document for GitLab, tier by tier.
Review-time savings come from what an AI reviewer can do to a pull request, not from how well it reads the diff. The per-provider capability gap, and how to audit it.