## Thinking Path
> - Paperclip is the open source app that people use to manage AI agents
for work.
> - Paperclip applies database migrations in numeric order.
> - Two branches can create the same migration number before either
branch merges.
> - The existing repository check can find duplicates only after both
histories are present in one checkout.
> - A pull request must compare its new migrations with the target
branch before merge.
> - This pull request adds that comparison to the existing PR policy
job.
> - The benefit is an early failure with exact renumbering instructions.
## Linked Issues or Issue Description
**What existing behavior does this improve?**
The PR policy check for files in `packages/db/src/migrations`.
**Current behavior**
A stale branch can add the same migration number as the target branch.
The existing check does not compare PR additions with the target branch
migration tip.
**Proposed behavior**
The policy job fails when a new PR migration number is not greater than
every migration on the target branch. The error names the conflict, the
next safe number, and the related files to update.
**Reason and benefit**
This prevents duplicate or out-of-order migration numbers from reaching
`master`. It also gives contributors and agents a direct repair
procedure.
**Breaking changes**
None. The change rejects migration numbering that is already unsafe.
## What Changed
- Added a dependency-free check that compares new PR migration files
with the target branch tip.
- Added the check to the existing PR policy job.
- Added tests for no-op, valid, duplicate, and lower-number cases.
## Verification
- `node --test '.github/scripts/tests/*.test.mjs'` passed 133 tests.
- `pnpm -r typecheck` passed.
- `pnpm build` passed.
- `pnpm test:run` passed 4,889 tests and failed 24 unrelated macOS path
and wildcard-listener tests that also affect the current `master`
checkout.
## Risks
- Low risk. The check reads Git history and does not modify migrations.
- The check permits gaps. It only requires each new migration number to
follow the target branch tip.
- The existing migration check continues to validate duplicate numbers,
snapshots, and journal entries inside the PR.
## Model Used
OpenAI Codex, GPT-5. The exact serving model ID and context-window size
are not exposed in this session. Reasoning, tool use, web access, and
code execution were enabled.
## Checklist
- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change (e.g. `docs/...`, `fix/...`)
and contains no internal Paperclip ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [ ] All Paperclip CI gates are green
- [x] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge
Co-authored-by: Paperclip <noreply@paperclip.ing>
Dotta