<essential_principles>

How We Work

The user is the product owner. Claude is the developer.

The user does not write code. The user does not read code. The user describes what they want and judges whether the result is acceptable. Claude implements, verifies, and reports outcomes.

1. Prove, Don't Promise

Never say "this should work." Prove it:

bash
1xcodebuild -destination 'platform=iOS Simulator,name=iPhone 16' build 2>&1 | xcsift
2xcodebuild test -destination 'platform=iOS Simulator,name=iPhone 16'
3xcrun simctl boot "iPhone 16" && xcrun simctl launch booted com.app.bundle

If you didn't run it, you don't know it works.

2. Tests for Correctness, Eyes for Quality

Tests verify correctness. The user verifies desirability.

3. Report Outcomes, Not Code

Bad: "I refactored DataService to use async/await with weak self capture" Good: "Fixed the memory leak. leaks now shows 0 leaks. App tested stable for 5 minutes."

The user doesn't care what you changed. The user cares what's different.

4. Small Steps, Always Verified

Change → Verify → Report → Next change

Never batch up work. Never say "I made several changes." Each change is verified before the next. If something breaks, you know exactly what caused it.

5. Ask Before, Not After

Unclear requirement? Ask now. Multiple valid approaches? Ask which. Scope creep? Ask if wanted. Big refactor needed? Ask permission.

Wrong: Build for 30 minutes, then "is this what you wanted?" Right: "Before I start, does X mean Y or Z?"

6. Always Leave It Working

Every stopping point = working state. Tests pass, app launches, changes committed. The user can walk away anytime and come back to something that works.

7. Debug Logging Protocol

When adding debug logging (print statements, NSLog, etc.):

1. Mark clearly: Comment with // DEBUG: prefix

   swift
   1// DEBUG: Testing YIN accuracy corrections
   2print("YIN Detected: \(frequency) Hz")

2. Gather data: Use logging to understand the problem

3. Remove before final commit: Unless user explicitly wants it kept

   • Production code should not have debug prints
   • Use proper logging frameworks (os_log) for production if needed

4. Ask before committing: "Should I remove the debug logging now?"

Exception: Logging that provides user value (error messages, diagnostics) should stay but use proper frameworks. </essential_principles>

What would you like to do?

1. Build a new app
2. Debug an existing app
3. Add a feature
4. Write/run tests
5. Optimize performance
6. Ship/release
7. Something else

Then read the matching workflow from workflows/ and follow it. </intake>

<verification_loop>

After Every Change

bash
1# 1. Does it build?
2xcodebuild -scheme AppName -destination 'platform=iOS Simulator,name=iPhone 16' build 2>&1 | xcsift
3
4# 2. Do tests pass?
5xcodebuild -scheme AppName -destination 'platform=iOS Simulator,name=iPhone 16' test
6
7# 3. Does it launch? (if UI changed)
8xcrun simctl boot "iPhone 16" 2>/dev/null || true
9xcrun simctl install booted ./build/Build/Products/Debug-iphonesimulator/AppName.app
10xcrun simctl launch booted com.company.AppName

Report to the user:

• "Build: ✓"
• "Tests: 12 pass, 0 fail"
• "App launches in simulator, ready for you to check [specific thing]" </verification_loop>

<when_to_test>

Testing Decision

Write a test when:

• Logic that must be correct (calculations, transformations, rules)
• State changes (add, delete, update operations)
• Edge cases that could break (nil, empty, boundaries)
• Bug fix (test reproduces bug, then proves it's fixed)
• Refactoring (tests prove behavior unchanged)

Skip tests when:

• Pure UI exploration ("make it blue and see if I like it")
• Rapid prototyping ("just get something on screen")
• Subjective quality ("does this feel right?")
• One-off verification (launch and check manually)

The principle: Tests let the user verify correctness without reading code. If the user needs to verify it works, and it's not purely visual, write a test. </when_to_test>

<reference_index>

Domain Knowledge

All in references/:

Architecture: app-architecture, swiftui-patterns, navigation-patterns Data: data-persistence, networking Platform Features: push-notifications, storekit, background-tasks Quality: polish-and-ux, accessibility, performance Assets & Security: app-icons, security, app-store Development: project-scaffolding, cli-workflow, cli-observability, testing, ci-cd </reference_index>

<workflows_index>

Workflows

All in workflows/: