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+# Instructions for AI agents
+
+## Commands
+
+Use the scripts in `package.json`, not the tools directly. The repository is a Yarn (Plug'n'Play) workspace.
+
+* Format: `yarn format` (Prettier; `yarn format:ci` lists unformatted files).
+* Lint: `yarn lint`
+* Test: `yarn test` (Vitest), e.g. `yarn vitest run src/web/e-stepper` for one package.
+* Build: `yarn build`
+* In a git worktree, run `yarn install` there first (the Plug'n'Play files are not in git).
+* Every change to a published package needs a changeset in `.changeset/`. Never put an ignored package and a non-ignored one in the same changeset (see `ignore` in `.changeset/config.json`): the release step rejects it and nothing is deployed.