merge-queue-readiness git:20260708.306185aA

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---
name: merge-queue-readiness
description: Pre-queue merge-group CI simulation. Triggered before adding a PR to a GitHub merge queue. Prevents merge-queue kick-outs from integration test failures.
---

# Merge Queue Readiness

## Trigger
Before adding the PR to the merge queue (or before the final push if the repo uses a merge queue).

## Protocol
1. **Fetch latest main:** `git fetch origin main`
2. **Create temporary simulation worktree (do NOT mutate the PR branch):**
   ```
   git worktree add /tmp/merge-sim origin/main
   cd /tmp/merge-sim
   git merge <pr-branch> --no-edit
   ```
3. **Run integration + unit tests against the merged result:**
   ```
   bun test tests/integration --timeout 120000
   bun test tests/unit --timeout 120000
   ```
   (Use per-file loops for hot modules per AGENTS.md invariant 6)
4. **If failures:** Fix on the PR branch, re-push, re-simulate
5. **Cleanup:** `git worktree remove --force /tmp/merge-sim`
6. **Only after simulation passes,** add PR to merge queue

## Why this matters
PR-branch CI and merge-group CI test DIFFERENT things:
- PR-branch: tests the PR head commit in isolation
- Merge-group: tests a temporary merge of PR head + latest main

Integration tests that pass on the PR branch may fail in merge-group context due to test interactions exposed by the merged result.

## Root cause
A `swarm ci-simulate` command would automate this (issue #1746 item 5). This playbook is the manual protocol.