第一次回滚：撤销你无法解释的 Agent PR

Your first AI pull request will often need rollback. Plan that rollback before you merge anything. You lack repo history on day one. Agents still produce large and confident diffs today. A rollback plan keeps that blast radius tiny. What first rollback actually means First rollback means undoing your own agent PR. It does not mean rewriting team history casually. You revert a branch you still control. You leave other people's commits completely untouched. Why juniors stall on revert You treat revert as an admission of failure. It is a safety move, not a performance review. You also wait for perfect understanding of every hunk. That wait lets CI keep building a bad branch. Step 1: Freeze merge before you diagnose Do not keep generating patches during a bad merge. Stop the agent, the pipeline, and extra pushes now. Mark the PR as draft if GitHub still allows it. Cancel running CI on that branch right now. Tell your reviewer the branch is under rollback. gh pr ready --undo gh run cancel --branch "$BRANCH" git status -sb Enter fullscreen mode Exit fullscreen mode Those three commands buy you quiet thinking time. You need that quiet before you touch git history. Step 2: Inventory every file the agent touched You cannot revert a change you cannot list. Ask git, not the chat log, for the truth. BASE="${BASE_SHA:-origin/main}" HEAD="${HEAD_SHA:-HEAD}" git fetch origin git diff --name-status "$BASE"..."$HEAD" git diff --stat "$BASE"..."$HEAD" git log --oneline "$BASE".."$HEAD" Enter fullscreen mode Exit fullscreen mode Save that inventory into a local file immediately. mkdir -p .onboarding git diff --name-status "$BASE"..."$HEAD" \ > .onboarding/first-pr-files.txt git diff "$BASE"..."$HEAD" \ > .onboarding/first-pr.patch Enter fullscreen mode Exit fullscreen mode Read the name-status list before any revert. Look for migrations, lockfiles, and generated assets. Read the patch in three passes You do not read the patch from top to bottom. You read it in three passes with git only. Read names first, then stats, then one scary file. Skip vendor folders until the end of the review. Stop when you cannot explain a hunk out loud. git diff --name-only "$BASE"...HEAD | wc -l git diff --stat "$BASE"...HEAD | tail -n 1 Enter fullscreen mode Exit fullscreen mode If the file count exceeds the ticket's expected paths, revert. A junior should not debug a thirty-file agent surprise. Step 3: Choose revert or fix-forward Use a hard table. Do not improvise under pressure. Signal Prefer revert Prefer fix-forward Files outside the ticket Yes No Tests red on your branch Yes Only if one test fails Schema or migration changed Yes No Reviewer already approved Ask first Maybe You cannot explain one hunk Yes No If two or more Yes cells fire, revert. Fix-forward is for a single, obvious typo only. Write the decision into the same onboarding folder. cat > .onboarding/rollback-decision.md "$OUT/branch.txt" git diff --name-status "$BASE"...HEAD > "$OUT/name-status.txt" git diff --stat "$BASE"...HEAD > "$OUT/stat.txt" git log --oneline "$BASE"..HEAD > "$OUT/commits.txt" echo "Risky paths:" > "$OUT/risks.txt" if command -v rg >/dev/null 2>&1; then rg -n -i "migration|schema|lock|generated|dist/" \ "$OUT/name-status.txt" >> "$OUT/risks.txt" || true else grep -Ei "migration|schema|lock|generated|dist/" \ "$OUT/name-status.txt" >> "$OUT/risks.txt" || true fi echo "Inventory written to $OUT" Enter fullscreen mode Exit fullscreen mode Label this as a proposed local helper, not team policy. Your new team may already have a revert runbook. Commit the script only if the team wants it. Do not sneak tooling into the rollback PR itself. Limitations This workflow assumes you still own the branch. It assumes main is protected and you can open drafts. It does not cover broken production traffic today. It does not cover signed commits you cannot reproduce. Revert can miss submodule pointers and LFS files. It can also miss squashed commits on a rewritten branch. The decision table is a heuristic, not a proof. Two yes cells do not replace a staff engineer's call. Free model access will not know your production topology. A free server will not hold your private incident facts. Do not paste secrets, tokens, or customer data into prompts. Who should not use this approach Skip this if you are not the PR author. Skip this if the change already shipped to customers. Skip this if the repo uses a required merge queue. Talk to the maintainer before any revert there. Skip this if you cannot run the README test command. A green revert you cannot test is still a guess. Juniors on regulated codebases should wait for a buddy. Pair on the revert and do not solo a schema undo. Close the loop on hour one Write three notes before you log off. What the agent changed outside the ticket. Which table signal made you choose revert. Which test command proved the tree was clean. Those notes become your second-day review checklist. They also keep the next agent session much smaller. Practice this workflow on a throwaway clone first. A free explain-only session can walk the inventory. Keep every git command in your own terminal.