Template updates

Copier records the template source (gh:justpenkit/justpen-mcp-dev-template), revision, and answers in .copier-answers.yml. Let Copier manage this file: editing its source, revision or answers by hand can break the comparison used for updates.

Update on a feature branch

Apply updates on a feature branch from a clean, committed worktree. Name the template release tag you are updating to:

git switch -c chore/update-template
uvx --from 'copier>=9.18.2,<10' copier update --vcs-ref=vX.Y.Z --defaults
git diff

Always pass --vcs-ref. --defaults reuses the recorded answers.

Copier merges template changes with project changes. Changes to the same lines create inline conflicts and unmerged Git entries. Resolve every conflict, then run:

make uv-lock
make setup

Review and ship the result through a PR. Do not use copier recopy as an update shortcut: it can overwrite project changes. Files this project moved or deleted, such as this guide (the template keeps it at docs/guides/template-updates.md), receive no template changes; port those by hand.

When a coding agent performs the update

The protected-files guard also applies to Copier updates. Claude Code and Codex must first render the update in a disposable checkout, present any direct pyproject.toml or uv.lock changes, and obtain your approval before applying them to the working project. Use the same exact template revision and answers for the preview and the approved update. Ordinary dependency resolution uses the make uv-* targets.

The guard reverts a copier update run by an agent that changes protected files, because copier is not an approved route. Run copier update from a terminal after approving the preview, or approve the result with make guard-accept-changes. See the agent guide for the guard and its limits. Follow the policy even when an indirect tool can write the file.

CI job names

Template updates can rename CI jobs. One check job replaced the quality job and the check (py3.x) matrix legs. If the repository requires status checks by name, the update's own pull request waits for checks that no longer run. Once check and integration pass on that pull request, change the required checks to those names, then merge.

Projects without .copier-answers.yml should generate a fresh reference project and migrate selected changes instead of inventing an answers file.