Tutorial

How the pieces fit

Onboarding puts the same rules in three places, and each one catches mistakes at a different moment:

1. While the code is written. AGENTS.md, CLAUDE.md, .github/copilot-instructions.md and .cursor/rules/ are read by your assistant on every request.
2. Before you push. review runs the rules a checker can decide on your machine, and /redline-review asks your assistant to apply the rest.
3. On the pull request. The gate runs the checker rules again, along with the pull request checklist, the secret scan and dependency review.

What you will do

1. Set up a playground, on this page: a new repository on your machine, onboarded by Redline.
2. Your first finding: plant four violations and run npx redlinegate@latest review.
3. Ask your assistant: the same review inside Claude Code, Copilot or Cursor.
4. Explain and fix: npx redlinegate@latest explain, then make the findings go away properly.
5. Push and stay current: what happens on the pull request, and how new rules reach you.

What you need

• Node 18 or later
• A terminal, such as iTerm2
• git

You do not need to install Redline. Every command runs the published package through npx, so you always get the current version.

Set up a playground

Create a repository

A new folder with one file and one commit, on your machine only.

mkdir redline-demo && cd redline-demo
git init -b main
npm init -y
mkdir src && echo 'export const ok = 1' > src/index.ts
git add -A && git commit -m "chore: initial commit"

npm: command not found or git: command not found? Install Node (npm comes with it) or git, open a new terminal, and run it again.

Onboard it

Run this on its own. The first time, npx asks Ok to proceed? (y); answer y.

$ npx redlinegate@latest init
  profile javascript-typescript
  ▲ this repository has no git remote, so Redline installed the rules and
    the local review only. The merge gate, branch policy, labels and security
    floor need a host: add a remote and run redline init again to install them

  Files  18 written
   + AGENTS.md
   + CLAUDE.md
   + .github/copilot-instructions.md
   + .claude/commands/redline-review.md
   + .redline.json
   …

  not committed — the files are in your working tree; commit them when you are ready

With no remote there is nowhere for a merge gate to run, so Redline installs what works on your machine and stops: it contacts no host, needs no credential and commits nothing. Add a remote later and run init again, and the gate and repository settings follow. Commit the files:

$ git add -A && git commit -m "chore: onboard redline"

Look at what it wrote

• AGENTS.md, CLAUDE.md, .github/copilot-instructions.md and .cursor/rules/: the rules, in the form each assistant reads.
• .claude/commands/, .github/prompts/ and .cursor/commands/: a /redline-review command for each assistant. Step 2 uses them.
• .redline.json: what was installed and at which version.

Open redline-demo as the workspace folder in your editor, so your assistant finds the rules and the commands. Then go to step 1.