The Startup Plan

A short written guide for people starting to build software with AI coding agents such as Claude Code, Codex, or Cursor. It lays out a six-step working loop, the four mistakes that cost us the most time, and what to do in your first week.

Read it: https://stylusnexus.github.io/startup-plan/

By Stylus Nexus.

Use it when

• You're about to start a project with an AI coding agent and want a working method before you write code
• Your agent says "done" and you don't trust it
• You want standing rules you can paste into your project's instructions file (see the prompts below)

What's here

• The loop: think, plan, build, verify, review, ship. Think widens the options and plan commits to one. Verify is a mechanical pass/fail; review needs judgment.
• Four failures: the mega-agent, the mega-CLAUDE.md, knowledge that lives only in a chat, and prompting by gut feel. One instinct sits behind all four.
• First moves: concrete things to do this week
• Where to go next: full-starter is a project template you fork to set the workflow up. agent-plugins holds skills you install into a project you already have.

What this is NOT

• Not software. It's a web page and two prompt files. There's nothing to install.
• Not a course or the full guide. It's the short version of two longer guides we wrote for ourselves, kept short on purpose.
• Not research. It's one team's experience, not a study or a benchmark.
• Not tied to one tool. Some examples use Claude Code file names. The loop and the failures apply to any coding agent.

Prompts

Both prompts on the page are also plain files, so you can grab one without opening a browser:

curl -s https://raw.githubusercontent.com/stylusnexus/startup-plan/main/prompts/validation-gate.md
curl -s https://raw.githubusercontent.com/stylusnexus/startup-plan/main/prompts/agentic-principles.md

• prompts/validation-gate.md — run before you scaffold anything, one time
• prompts/agentic-principles.md — paste into CLAUDE.md / AGENTS.md as standing rules

Editing

Single self-contained index.html, no build step, no dependencies. Served via GitHub Pages from main.

Each prompt lives in two places: a file under prompts/ and a copy on the page. After editing either, run python3 scripts/check-sync.py. It fails if they differ.

License

MIT. See LICENSE. You can reuse the prompts and the page; keep the copyright notice.