/build

What to build: {{arguments}}

Check first, before spawning anything. This command needs a git repository, a remote you can push to, and gh logged in. No repository: say so and offer to make the change in place, with tests, and no worktree or pull request. A repository but no remote or no gh: run steps 1 to 4, stop at the local commit, and report the branch as ready to push.

1. Work from the plan path or the issue number you were given, and say which in your first message. Never search for a plan: /plan renames the approved file and hands over its path, and a plan found by date is as likely to be last week’s. With neither a path nor an issue, ask for one. Give the builder the absolute plan path and tell it to copy the file into its worktree and commit it — a worktree carries no untracked file, and the plan belongs in the PR.
2. Spawn the builder agent with the plan or issue text, the repository path, the base branch, and the attribution trailer your tool supplies. Its definition already carries the standing brief — a worktree off the base branch per worktree-per-agent, the repository’s own instructions read first, tests with every change, the repository’s gate, one local Conventional Commit — so retype none of it. Give it the scope instead: the files it may touch and the ones it must leave alone.
3. Run the gate yourself in the worktree it names, with the repository’s own commands. Never take an agent’s word for a verifier; you read the exit status, not its account of the run. Red means you fix it or hand the finding back, never that you push anyway.
4. Check the commit before it leaves the machine: a Conventional Commit title, a body ending in Closes #N and the attribution trailer, and nothing in the diff that fails to trace to the issue.
5. Push the branch and open the pull request with gh pr create, based on the default branch, never pushing to that branch directly. Body: a few bullets on what and why, Closes #N, and the generated-with line your tool supplies.

Report the pull request URL, the tail of your own gate run, and anything still open: a decision taken on the user’s behalf, a step left unfinished, a test that had to be skipped.