agent-skills: 5 Patterns That Actually Work

addyosmani/agent-skills (Google Chrome team lead) hit 68K stars in 2 weeks. The repo distills production patterns for AI coding agents.

Pattern 1: “Test-First Agent”

Don’t ask the agent to “build a feature.” Ask it to:

1. Write failing tests
2. Confirm tests fail
3. Implement
4. Confirm tests pass
5. Refactor

You are writing a feature for a billing system.
1. First, write tests in tests/billing.test.ts
2. Run `npm test` — confirm RED
3. Implement the feature
4. Run `npm test` — confirm GREEN
5. Refactor if needed

Pattern 2: “Constraint Documents”

The agent doesn’t know your project’s hidden rules. Tell it:

# CONSTRAINTS.md
- All API endpoints must return JSON
- No console.log in production code
- All PRs must include migration files
- Tests must run in <30s

Pattern 3: “Read-Before-Edit”

Force the agent to read the file completely before editing:

Before changing any file:
1. cat the file
2. Identify all imports, exports, side effects
3. Write a 1-line summary of what it does
4. THEN propose your edit

Pattern 4: “Diff-First Approval”

Generate the diff first, ask for approval, then apply:

For every code change:
1. Show the diff
2. WAIT for my explicit "apply" 
3. Never auto-apply

Pattern 5: “Incremental Rollout”

Don’t ask for 10 files at once:

Make ONE change at a time:
1. First change → verify → commit
2. Second change → verify → commit
3. ...

Sources

• addyosmani/agent-skills: 68K stars
• r/ClaudeAI: 1.4k upvotes
• HN: 2,100 points