Scaffold CLI

Scaffold CLI

• IS: bootstrapping a brand-new TypeScript CLI or npm package (Node 24, TypeScript 7) from the pinned templates in references/, through to a green first CI run and a package npm can publish over OIDC.
• IS NOT: a Next.js web app (use scaffold-nextjs), folder structure or module contracts for an existing codebase (use codebase-architecture), auditing an existing CLI's ergonomics (use dx-audit), or shipping a release of an existing package (use autoship).

The templates encode the house toolchain. Substitute project values and verify template APIs against installed package versions; repair proven incompatibilities instead of blindly reproducing them. The toolchain is the opinion: tsdown not tsup, vitest not jest, oxlint and oxfmt via ultracite not eslint or prettier, node:util styleText not chalk, @clack/prompts not ora. Swapping any of them or restructuring the layout produces a repo the templates' notes no longer describe.

Reference Files

Scaffold Workflow

Copy this checklist to track progress:

Scaffold progress:
- [ ] Step 1: Gather project info
- [ ] Step 2: Create directory structure
- [ ] Step 3: Generate config files
- [ ] Step 4: Generate source files
- [ ] Step 5: Generate docs and skill
- [ ] Step 6: Run post-scaffold commands
- [ ] Step 7: Validate scaffold
- [ ] Step 8: Bootstrap GitHub and npm (with the user's go-ahead)

Step 1: Gather project info

Ask only for what the user didn't provide:

{{repo}} must be the exact GitHub owner/name: npm provenance rejects a publish whose repository.url differs from the repo it came from.

Step 2: Create directory structure

{{name}}/
  .changeset/
  .github/
    workflows/
  src/
  skills/{{bin}}/

Step 3: Generate config files

Load references/scaffold-configs.md. Generate every file there, replacing each {{placeholder}}:

package.json, tsconfig.json, tsdown.config.ts, .gitignore, LICENSE.md, .changeset/config.json, .changeset/README.md, .github/workflows/ci.yml, .github/workflows/npm-publish.yml

Step 4: Generate source files

Load references/scaffold-source.md. Generate:

• src/cli.ts: Commander entry point with agent-friendly defaults (--output text|json, --no-input, stdout data / stderr log split, JSON error envelope)
• src/index.ts: Public API exports
• src/types.ts: Shared type definitions

When a command takes an identifier, path, or URL, or mutates state, also load references/agent-friendly-cli.md and copy the matching pinned pattern. Skip it for a CLI with no such command.

Step 5: Generate docs and skill

From the same references/scaffold-source.md, generate:

• AGENTS.md: commands, architecture, gotchas, agent invariants
• README.md: install, usage, API, agent skill install, license
• skills/{{bin}}/SKILL.md: agent skill definition

Do not create the CLAUDE.md symlink here; Step 6 creates it exactly once.

Step 6: Run post-scaffold commands

Load references/post-scaffold.md. Run the command sequence in the order given, including the lefthook.yml overwrite between ultracite init and the first commit.

Step 7: Validate scaffold

Run the validation checklist in references/post-scaffold.md. Every item is a command whose output is the evidence; the checklist includes publint, arethetypeswrong, the hook exercised against real files, and the placeholder sweep.

Step 8: Bootstrap GitHub and npm

For a local scaffold, stop after Step 7. If the user already requested remote setup or publication, carry out that authorized scope. Otherwise present the prepared repository/package identity before asking to create or publish it. Otherwise follow "Bootstrap GitHub and npm" in references/post-scaffold.md: create and push the repo, enable Actions-created PRs, publish 0.0.1 once by hand so the package exists, then register the workflow as a trusted publisher. Terminal evidence is a green CI run on the pushed commit and npm view {{name}} version printing 0.0.1. From here every release belongs to autoship.

Dependencies

Runtime: @clack/prompts, commander

Development (in the package.json template): @changesets/cli, @types/node, tsdown, typescript, vitest

Added by ultracite init, never listed by hand: ultracite (pinned exact by init), oxlint, oxfmt, lefthook, plus the check, fix, and prepare scripts. By-hand entries produce duplicate scripts and version skew against what init installs.

Gotchas

• tsdown emits .mjs by default. With platform: node (the default) fixedExtension is on, so a config without outputOptions.entryFileNames: "[name].js" builds dist/cli.mjs, dist/index.mjs, and dist/index.d.mts, and bin and exports point at files that do not exist. The outputOptions block in the template is what keeps them .js; do not trim it as noise.
• No shebang in src/cli.ts. tsdown's banner injects #!/usr/bin/env node; a source shebang doubles it in dist/cli.js. The two build entries stay separate: the CLI entry has the banner and dts: false, the library entry has dts: true and no banner.
• ultracite init --quiet without --linter oxlint installs Biome. Quiet mode defaults the linter to Biome instead of prompting, so the repo silently ends up on the wrong toolchain. Pass every flag in the post-scaffold command.
• git init before ultracite init. Init adds prepare: lefthook install and runs it at once; lefthook install writes into .git/hooks and fails without a repo.
• Replace the generated lefthook.yml before the first commit. It runs npx ultracite fix with no file arguments, so a one-line change reformats the whole tree (31 files in the reference repo), and its **/*.ts globs never match root files, so package.json and tsdown.config.ts edits bypass the hook entirely. Adding {staged_files} alone makes it worse: a JSON-only commit (the shape of the changesets bot's Version Packages commit) then hits oxlint with no lintable file and exits 1. Use the version in references/post-scaffold.md, with *.{...} globs, never **/.
• touch <file> && git add <file> stages nothing. An unchanged file has no staged diff, so the hook skips and the check proves nothing. Exercise the hook with npx lefthook run pre-commit --file <path>.
• "test": "vitest run" without --passWithNoTests exits 1 on a repo with zero test files, so the first CI run goes red.
• @changesets/cli@3 pairs with changesets/action@v2 and the publish-script: input. @v1 cannot drive changesets v3, and @v2 given the v1 publish: input versions the package and then completes green without publishing. The templates carry the matching pair; do not downgrade one side.
• npm cannot register a trusted publisher for a package that does not exist yet. The first release run fails E404 or ENEEDAUTH until Step 8's one-time manual npm publish has created the package and the workflow is registered. That publish happens before any changeset exists, so it is the one manual publish autoship's rules do not forbid.
• Node 22 ships npm 10.9.x; OIDC publishing needs npm 11.5.1 or later. Node 24 ships npm 11.19, which is why both workflows pin node-version: 24. Lowering it to 22 breaks publishing with ENEEDAUTH.
• Agent-facing output is a format contract. Data on stdout, logs and progress on stderr; a stray console.log breaks a consumer parsing --output json. Never prompt when stdin is not a TTY: honor --no-input and take every value as a flag, or the process hangs under a pipe.

Related Skills

• autoship: every release after the bootstrap publish: changeset, CI watch, Version Packages PR, publish verification, and diagnosis of a release that did not publish.
• dx-audit: audit the CLI's flags, errors, and types once real commands exist.
• agents-md: grow the generated AGENTS.md as the codebase gains structure.
• readme-creator: rewrite the README once there is a real usage story to tell.

Maintenance only: evals/evals.json contains regression scenarios for changes to this skill; it does not load during a user task.