project-builder — Claude Code skill: plan, build, debug projects
Walks a project through design, scaffolding, incremental building, preview checks and systematic debugging. Fits requests like a dashboard, a web app or a recurring job.
npx skills add Starchild-ai-agent/official-skills --skill project-builder -a claude-codeWhat project-builder does
Vague requests get turned into a spec first. The skill picks an architecture from a decision tree: periodic reports become scheduled tasks, a live interface goes to a preview server, one-off analysis stays inline, and a reusable tool turns into a script. For anything beyond small work it lays out the data flow, the chosen architecture, a cost estimate per run and known limits before code appears.
Then comes a fixed scaffold at output/projects/{slug}/ holding project.yaml, PROJECT.md, .env.example and a src/ folder. The project type decides the entry point: src/run.py for a task, src/server.py for a service, src/main.py for a script, src/index.html or src/app.py for a preview. Any environment variable the code reads must land in .env.example in the same edit.
Platform references are read before building: config/context/references/sc-proxy.md for outside API calls, preview-guide.md for previews, scheduled-tasks-guide.md for recurring work. Every external request runs through sc-proxy, which bills per call and enforces rate limits, so skipping that file leads straight to 401s. Pages users will see also have to go through the ui-design skill — build HTML without it and you get the usual generic output.
What it helps with
- turn a fuzzy request into staged work with a fixed architecture
- scaffold a project with config, docs and a sample env file
- serve a dashboard in preview and check that it loads
- schedule a recurring job and watch its logs
- trace a bug that only shows up after local runs
Example prompts for the agent
- Build a sales dashboard from this API — show me the plan and cost per run first
- Write a script that pulls a daily summary and sends me the report
- The preview broke — debug it step by step instead of guessing
How to install project-builder
1Skills CLI (Vercel)
npx skills add Starchild-ai-agent/official-skills --skill project-builder -a claude-code2Manually: put the files in place
~/.claude/skills/project-builder/SKILL.mdCopy the whole skill folder; for one project use .claude/skills/project-builder/
1Skills CLI (Vercel)
npx skills add Starchild-ai-agent/official-skills --skill project-builder -a codex2Manually: put the files in place
.agents/skills/project-builder/SKILL.mdFor all projects use ~/.agents/skills/
1Skills CLI (Vercel)
npx skills add Starchild-ai-agent/official-skills --skill project-builder -a cursor2Manually: put the files in place
.cursor/skills/project-builder/SKILL.mdCursor also reads .agents/skills/ and .claude/skills/
1GitHub CLI
gh skill install Starchild-ai-agent/official-skills project-builder2Manually: put the files in place
.github/skills/project-builder/SKILL.md1Skills CLI (Vercel)
npx skills add Starchild-ai-agent/official-skills --skill project-builder -a gemini-cli2Platform CLI
gemini skills install https://github.com/Starchild-ai-agent/official-skills --path project-builderManually: put the files in place
.devin/skills/project-builder/SKILL.mdThe legacy .windsurf/skills/ path still works
Skills CLI (Vercel)
npx skills add Starchild-ai-agent/official-skills --skill project-builder -a opencodeClaude.ai
Zip the folder and upload it in Settings → Capabilities → Skills
Step by step, with commands for each platform: How to install skills in Claude Code: five ways
Questions about project-builder
How do I install project-builder in Claude Code?
Run npx skills add Starchild-ai-agent/official-skills --skill project-builder -a claude-code. The skill lands at ~/.claude/skills/project-builder/SKILL.md.
What does project-builder do?
It carries a project through design, scaffolding, incremental build, preview verification and debugging. It also keeps the folder layout in a shape that can be published later.
Why does an API call fail with 401?
External requests go through sc-proxy, and the skill tells you to read config/context/references/sc-proxy.md first. Missing that step is a common source of auth errors, broken paths and preview failures.
