msd-core/get-shit-done/references/checkpoints.md

<overview>
Plans execute autonomously. Checkpoints formalize the interaction points where human verification or decisions are needed.

**Core principle:** Claude automates everything with CLI/API. Checkpoints are for verification and decisions, not manual work.

**Golden rules:**
1. **If Claude can run it, Claude runs it** - Never ask user to execute CLI commands, start servers, or run builds
2. **Claude sets up the verification environment** - Start dev servers, seed databases, configure env vars
3. **User only does what requires human judgment** - Visual checks, UX evaluation, "does this feel right?"
4. **Secrets come from user, automation comes from Claude** - Ask for API keys, then Claude uses them via CLI
</overview>

<checkpoint_types>

<type name="human-verify">
## checkpoint:human-verify (Most Common - 90%)

**When:** Claude completed automated work, human confirms it works correctly.

**Use for:**
- Visual UI checks (layout, styling, responsiveness)
- Interactive flows (click through wizard, test user flows)
- Functional verification (feature works as expected)
- Audio/video playback quality
- Animation smoothness
- Accessibility testing

**Structure:**
```xml
<task type="checkpoint:human-verify" gate="blocking">
  <what-built>[What Claude automated and deployed/built]</what-built>
  <how-to-verify>
    [Exact steps to test - URLs, commands, expected behavior]
  </how-to-verify>
  <resume-signal>[How to continue - "approved", "yes", or describe issues]</resume-signal>
</task>
```

**Key elements:**
- `<what-built>`: What Claude automated (deployed, built, configured)
- `<how-to-verify>`: Exact steps to confirm it works (numbered, specific)
- `<resume-signal>`: Clear indication of how to continue

**Example: Vercel Deployment**
```xml
<task type="auto">
  <name>Deploy to Vercel</name>
  <files>.vercel/, vercel.json</files>
  <action>Run `vercel --yes` to create project and deploy. Capture deployment URL from output.</action>
  <verify>vercel ls shows deployment, curl {url} returns 200</verify>
  <done>App deployed, URL captured</done>
</task>

<task type="checkpoint:human-verify" gate="blocking">
  <what-built>Deployed to Vercel at https://myapp-abc123.vercel.app</what-built>
  <how-to-verify>
    Visit https://myapp-abc123.vercel.app and confirm:
    - Homepage loads without errors
    - Login form is visible
    - No console errors in browser DevTools
  </how-to-verify>
  <resume-signal>Type "approved" to continue, or describe issues to fix</resume-signal>
</task>
```

**Example: UI Component**
```xml
<task type="auto">
  <name>Build responsive dashboard layout</name>
  <files>src/components/Dashboard.tsx, src/app/dashboard/page.tsx</files>
  <action>Create dashboard with sidebar, header, and content area. Use Tailwind responsive classes for mobile.</action>
  <verify>npm run build succeeds, no TypeScript errors</verify>
  <done>Dashboard component builds without errors</done>
</task>

<task type="auto">
  <name>Start dev server for verification</name>
  <action>Run `npm run dev` in background, wait for "ready" message, capture port</action>
  <verify>curl http://localhost:3000 returns 200</verify>
  <done>Dev server running at http://localhost:3000</done>
</task>

<task type="checkpoint:human-verify" gate="blocking">
  <what-built>Responsive dashboard layout - dev server running at http://localhost:3000</what-built>
  <how-to-verify>
    Visit http://localhost:3000/dashboard and verify:
    1. Desktop (>1024px): Sidebar left, content right, header top
    2. Tablet (768px): Sidebar collapses to hamburger menu
    3. Mobile (375px): Single column layout, bottom nav appears
    4. No layout shift or horizontal scroll at any size
  </how-to-verify>
  <resume-signal>Type "approved" or describe layout issues</resume-signal>
</task>
```

**Key pattern:** Claude starts the dev server BEFORE the checkpoint. User only needs to visit the URL.

**Example: Xcode Build**
```xml
<task type="auto">
  <name>Build macOS app with Xcode</name>
  <files>App.xcodeproj, Sources/</files>
  <action>Run `xcodebuild -project App.xcodeproj -scheme App build`. Check for compilation errors in output.</action>
  <verify>Build output contains "BUILD SUCCEEDED", no errors</verify>
  <done>App builds successfully</done>
</task>

<task type="checkpoint:human-verify" gate="blocking">
  <what-built>Built macOS app at DerivedData/Build/Products/Debug/App.app</what-built>
  <how-to-verify>
    Open App.app and test:
    - App launches without crashes
    - Menu bar icon appears
    - Preferences window opens correctly
    - No visual glitches or layout issues
  </how-to-verify>
  <resume-signal>Type "approved" or describe issues</resume-signal>
</task>
```
</type>

<type name="decision">
## checkpoint:decision (9%)

**When:** Human must make choice that affects implementation direction.

**Use for:**
- Technology selection (which auth provider, which database)
- Architecture decisions (monorepo vs separate repos)
- Design choices (color scheme, layout approach)
- Feature prioritization (which variant to build)
- Data model decisions (schema structure)

**Structure:**
```xml
<task type="checkpoint:decision" gate="blocking">
  <decision>[What's being decided]</decision>
  <context>[Why this decision matters]</context>
  <options>
    <option id="option-a">
      <name>[Option name]</name>
      <pros>[Benefits]</pros>
      <cons>[Tradeoffs]</cons>
    </option>
    <option id="option-b">
      <name>[Option name]</name>
      <pros>[Benefits]</pros>
      <cons>[Tradeoffs]</cons>
    </option>
  </options>
  <resume-signal>[How to indicate choice]</resume-signal>
</task>
```

**Key elements:**
- `<decision>`: What's being decided
- `<context>`: Why this matters
- `<options>`: Each option with balanced pros/cons (not prescriptive)
- `<resume-signal>`: How to indicate choice

**Example: Auth Provider Selection**
```xml
<task type="checkpoint:decision" gate="blocking">
  <decision>Select authentication provider</decision>
  <context>
    Need user authentication for the app. Three solid options with different tradeoffs.
  </context>
  <options>
    <option id="supabase">
      <name>Supabase Auth</name>
      <pros>Built-in with Supabase DB we're using, generous free tier, row-level security integration</pros>
      <cons>Less customizable UI, tied to Supabase ecosystem</cons>
    </option>
    <option id="clerk">
      <name>Clerk</name>
      <pros>Beautiful pre-built UI, best developer experience, excellent docs</pros>
      <cons>Paid after 10k MAU, vendor lock-in</cons>
    </option>
    <option id="nextauth">
      <name>NextAuth.js</name>
      <pros>Free, self-hosted, maximum control, widely adopted</pros>
      <cons>More setup work, you manage security updates, UI is DIY</cons>
    </option>
  </options>
  <resume-signal>Select: supabase, clerk, or nextauth</resume-signal>
</task>
```

**Example: Database Selection**
```xml
<task type="checkpoint:decision" gate="blocking">
  <decision>Select database for user data</decision>
  <context>
    App needs persistent storage for users, sessions, and user-generated content.
    Expected scale: 10k users, 1M records first year.
  </context>
  <options>
    <option id="supabase">
      <name>Supabase (Postgres)</name>
      <pros>Full SQL, generous free tier, built-in auth, real-time subscriptions</pros>
      <cons>Vendor lock-in for real-time features, less flexible than raw Postgres</cons>
    </option>
    <option id="planetscale">
      <name>PlanetScale (MySQL)</name>
      <pros>Serverless scaling, branching workflow, excellent DX</pros>
      <cons>MySQL not Postgres, no foreign keys in free tier</cons>
    </option>
    <option id="convex">
      <name>Convex</name>
      <pros>Real-time by default, TypeScript-native, automatic caching</pros>
      <cons>Newer platform, different mental model, less SQL flexibility</cons>
    </option>
  </options>
  <resume-signal>Select: supabase, planetscale, or convex</resume-signal>
</task>
```
</type>

<type name="human-action">
## checkpoint:human-action (1% - Rare)

**When:** Action has NO CLI/API and requires human-only interaction, OR Claude hit an authentication gate during automation.

**Use ONLY for:**
- **Authentication gates** - Claude tried to use CLI/API but needs credentials to continue (this is NOT a failure)
- Email verification links (account creation requires clicking email)
- SMS 2FA codes (phone verification)
- Manual account approvals (platform requires human review before API access)
- Credit card 3D Secure flows (web-based payment authorization)
- OAuth app approvals (some platforms require web-based approval)

**Do NOT use for pre-planned manual work:**
- Manually deploying to Vercel (use `vercel` CLI - auth gate if needed)
- Manually creating Stripe webhooks (use Stripe API - auth gate if needed)
- Manually creating databases (use provider CLI - auth gate if needed)
- Running builds/tests manually (use Bash tool)
- Creating files manually (use Write tool)

**Structure:**
```xml
<task type="checkpoint:human-action" gate="blocking">
  <action>[What human must do - Claude already did everything automatable]</action>
  <instructions>
    [What Claude already automated]
    [The ONE thing requiring human action]
  </instructions>
  <verification>[What Claude can check afterward]</verification>
  <resume-signal>[How to continue]</resume-signal>
</task>
```

**Key principle:** Claude automates EVERYTHING possible first, only asks human for the truly unavoidable manual step.

**Example: Email Verification**
```xml
<task type="auto">
  <name>Create SendGrid account via API</name>
  <action>Use SendGrid API to create subuser account with provided email. Request verification email.</action>
  <verify>API returns 201, account created</verify>
  <done>Account created, verification email sent</done>
</task>

<task type="checkpoint:human-action" gate="blocking">
  <action>Complete email verification for SendGrid account</action>
  <instructions>
    I created the account and requested verification email.
    Check your inbox for SendGrid verification link and click it.
  </instructions>
  <verification>SendGrid API key works: curl test succeeds</verification>
  <resume-signal>Type "done" when email verified</resume-signal>
</task>
```

**Example: Credit Card 3D Secure**
```xml
<task type="auto">
  <name>Create Stripe payment intent</name>
  <action>Use Stripe API to create payment intent for $99. Generate checkout URL.</action>
  <verify>Stripe API returns payment intent ID and URL</verify>
  <done>Payment intent created</done>
</task>

<task type="checkpoint:human-action" gate="blocking">
  <action>Complete 3D Secure authentication</action>
  <instructions>
    I created the payment intent: https://checkout.stripe.com/pay/cs_test_abc123
    Visit that URL and complete the 3D Secure verification flow with your test card.
  </instructions>
  <verification>Stripe webhook receives payment_intent.succeeded event</verification>
  <resume-signal>Type "done" when payment completes</resume-signal>
</task>
```

**Example: Authentication Gate (Dynamic Checkpoint)**
```xml
<task type="auto">
  <name>Deploy to Vercel</name>
  <files>.vercel/, vercel.json</files>
  <action>Run `vercel --yes` to deploy</action>
  <verify>vercel ls shows deployment, curl returns 200</verify>
</task>

<!-- If vercel returns "Error: Not authenticated", Claude creates checkpoint on the fly -->

<task type="checkpoint:human-action" gate="blocking">
  <action>Authenticate Vercel CLI so I can continue deployment</action>
  <instructions>
    I tried to deploy but got authentication error.
    Run: vercel login
    This will open your browser - complete the authentication flow.
  </instructions>
  <verification>vercel whoami returns your account email</verification>
  <resume-signal>Type "done" when authenticated</resume-signal>
</task>

<!-- After authentication, Claude retries the deployment -->

<task type="auto">
  <name>Retry Vercel deployment</name>
  <action>Run `vercel --yes` (now authenticated)</action>
  <verify>vercel ls shows deployment, curl returns 200</verify>
</task>
```

**Key distinction:** Authentication gates are created dynamically when Claude encounters auth errors during automation. They're NOT pre-planned - Claude tries to automate first, only asks for credentials when blocked.
</type>
</checkpoint_types>

<execution_protocol>

When Claude encounters `type="checkpoint:*"`:

1. **Stop immediately** - do not proceed to next task
2. **Display checkpoint clearly** using the format below
3. **Wait for user response** - do not hallucinate completion
4. **Verify if possible** - check files, run tests, whatever is specified
5. **Resume execution** - continue to next task only after confirmation

**For checkpoint:human-verify:**
```
╔═══════════════════════════════════════════════════════╗
║  CHECKPOINT: Verification Required                    ║
╚═══════════════════════════════════════════════════════╝

Progress: 5/8 tasks complete
Task: Responsive dashboard layout

Built: Responsive dashboard at /dashboard

How to verify:
  1. Run: npm run dev
  2. Visit: http://localhost:3000/dashboard
  3. Desktop (>1024px): Sidebar visible, content fills remaining space
  4. Tablet (768px): Sidebar collapses to icons
  5. Mobile (375px): Sidebar hidden, hamburger menu appears

────────────────────────────────────────────────────────
→ YOUR ACTION: Type "approved" or describe issues
────────────────────────────────────────────────────────
```

**For checkpoint:decision:**
```
╔═══════════════════════════════════════════════════════╗
║  CHECKPOINT: Decision Required                        ║
╚═══════════════════════════════════════════════════════╝

Progress: 2/6 tasks complete
Task: Select authentication provider

Decision: Which auth provider should we use?

Context: Need user authentication. Three options with different tradeoffs.

Options:
  1. supabase - Built-in with our DB, free tier
     Pros: Row-level security integration, generous free tier
     Cons: Less customizable UI, ecosystem lock-in

  2. clerk - Best DX, paid after 10k users
     Pros: Beautiful pre-built UI, excellent documentation
     Cons: Vendor lock-in, pricing at scale

  3. nextauth - Self-hosted, maximum control
     Pros: Free, no vendor lock-in, widely adopted
     Cons: More setup work, DIY security updates

────────────────────────────────────────────────────────
→ YOUR ACTION: Select supabase, clerk, or nextauth
────────────────────────────────────────────────────────
```

**For checkpoint:human-action:**
```
╔═══════════════════════════════════════════════════════╗
║  CHECKPOINT: Action Required                          ║
╚═══════════════════════════════════════════════════════╝

Progress: 3/8 tasks complete
Task: Deploy to Vercel

Attempted: vercel --yes
Error: Not authenticated. Please run 'vercel login'

What you need to do:
  1. Run: vercel login
  2. Complete browser authentication when it opens
  3. Return here when done

I'll verify: vercel whoami returns your account

────────────────────────────────────────────────────────
→ YOUR ACTION: Type "done" when authenticated
────────────────────────────────────────────────────────
```
</execution_protocol>

<authentication_gates>

**Critical:** When Claude tries CLI/API and gets auth error, this is NOT a failure - it's a gate requiring human input to unblock automation.

**Pattern:** Claude tries automation → auth error → creates checkpoint → you authenticate → Claude retries → continues

**Gate protocol:**
1. Recognize it's not a failure - missing auth is expected
2. Stop current task - don't retry repeatedly
3. Create checkpoint:human-action dynamically
4. Provide exact authentication steps
5. Verify authentication works
6. Retry the original task
7. Continue normally

**Example execution flow (Vercel auth gate):**

```
Claude: Running `vercel --yes` to deploy...

Error: Not authenticated. Please run 'vercel login'

╔═══════════════════════════════════════════════════════╗
║  CHECKPOINT: Action Required                          ║
╚═══════════════════════════════════════════════════════╝

Progress: 2/8 tasks complete
Task: Deploy to Vercel

Attempted: vercel --yes
Error: Not authenticated

What you need to do:
  1. Run: vercel login
  2. Complete browser authentication

I'll verify: vercel whoami returns your account

────────────────────────────────────────────────────────
→ YOUR ACTION: Type "done" when authenticated
────────────────────────────────────────────────────────

User: done

Claude: Verifying authentication...
Running: vercel whoami
✓ Authenticated as: user@example.com

Retrying deployment...
Running: vercel --yes
✓ Deployed to: https://myapp-abc123.vercel.app

Task 3 complete. Continuing to task 4...
```

**Key distinction:**
- Pre-planned checkpoint: "I need you to do X" (wrong - Claude should automate)
- Auth gate: "I tried to automate X but need credentials" (correct - unblocks automation)

</authentication_gates>

<automation_reference>

**The rule:** If it has CLI/API, Claude does it. Never ask human to perform automatable work.

## Service CLI Reference

| Service | CLI/API | Key Commands | Auth Gate |
|---------|---------|--------------|-----------|
| Vercel | `vercel` | `--yes`, `env add`, `--prod`, `ls` | `vercel login` |
| Railway | `railway` | `init`, `up`, `variables set` | `railway login` |
| Fly | `fly` | `launch`, `deploy`, `secrets set` | `fly auth login` |
| Stripe | `stripe` + API | `listen`, `trigger`, API calls | API key in .env |
| Supabase | `supabase` | `init`, `link`, `db push`, `gen types` | `supabase login` |
| Upstash | `upstash` | `redis create`, `redis get` | `upstash auth login` |
| PlanetScale | `pscale` | `database create`, `branch create` | `pscale auth login` |
| GitHub | `gh` | `repo create`, `pr create`, `secret set` | `gh auth login` |
| Node | `npm`/`pnpm` | `install`, `run build`, `test`, `run dev` | N/A |
| Xcode | `xcodebuild` | `-project`, `-scheme`, `build`, `test` | N/A |
| Convex | `npx convex` | `dev`, `deploy`, `env set`, `env get` | `npx convex login` |

## Environment Variable Automation

**Env files:** Use Write/Edit tools. Never ask human to create .env manually.

**Dashboard env vars via CLI:**

| Platform | CLI Command | Example |
|----------|-------------|---------|
| Convex | `npx convex env set` | `npx convex env set OPENAI_API_KEY sk-...` |
| Vercel | `vercel env add` | `vercel env add STRIPE_KEY production` |
| Railway | `railway variables set` | `railway variables set API_KEY=value` |
| Fly | `fly secrets set` | `fly secrets set DATABASE_URL=...` |
| Supabase | `supabase secrets set` | `supabase secrets set MY_SECRET=value` |

**Pattern for secret collection:**
```xml
<!-- WRONG: Asking user to add env vars in dashboard -->
<task type="checkpoint:human-action">
  <action>Add OPENAI_API_KEY to Convex dashboard</action>
  <instructions>Go to dashboard.convex.dev → Settings → Environment Variables → Add</instructions>
</task>

<!-- RIGHT: Claude asks for value, then adds via CLI -->
<task type="checkpoint:human-action">
  <action>Provide your OpenAI API key</action>
  <instructions>
    I need your OpenAI API key to configure the Convex backend.
    Get it from: https://platform.openai.com/api-keys
    Paste the key (starts with sk-)
  </instructions>
  <verification>I'll add it via `npx convex env set` and verify it's configured</verification>
  <resume-signal>Paste your API key</resume-signal>
</task>

<task type="auto">
  <name>Configure OpenAI key in Convex</name>
  <action>Run `npx convex env set OPENAI_API_KEY {user-provided-key}`</action>
  <verify>`npx convex env get OPENAI_API_KEY` returns the key (masked)</verify>
</task>
```

## Dev Server Automation

**Claude starts servers, user visits URLs:**

| Framework | Start Command | Ready Signal | Default URL |
|-----------|---------------|--------------|-------------|
| Next.js | `npm run dev` | "Ready in" or "started server" | http://localhost:3000 |
| Vite | `npm run dev` | "ready in" | http://localhost:5173 |
| Convex | `npx convex dev` | "Convex functions ready" | N/A (backend only) |
| Express | `npm start` | "listening on port" | http://localhost:3000 |
| Django | `python manage.py runserver` | "Starting development server" | http://localhost:8000 |

### Server Lifecycle Protocol

**Starting servers:**
```bash
# Run in background, capture PID for cleanup
npm run dev &
DEV_SERVER_PID=$!

# Wait for ready signal (max 30s)
timeout 30 bash -c 'until curl -s localhost:3000 > /dev/null 2>&1; do sleep 1; done'
```

**Port conflicts:**
If default port is in use, check what's running and either:
1. Kill the existing process if it's stale: `lsof -ti:3000 | xargs kill`
2. Use alternate port: `npm run dev -- --port 3001`

**Server stays running** for the duration of the checkpoint. After user approves, server continues running for subsequent tasks. Only kill explicitly if:
- Plan is complete and no more verification needed
- Switching to production deployment
- Port needed for different service

**Pattern:**
```xml
<!-- Claude starts server before checkpoint -->
<task type="auto">
  <name>Start dev server</name>
  <action>Run `npm run dev` in background, wait for ready signal</action>
  <verify>curl http://localhost:3000 returns 200</verify>
  <done>Dev server running</done>
</task>

<!-- User only visits URL -->
<task type="checkpoint:human-verify">
  <what-built>Feature X - dev server running at http://localhost:3000</what-built>
  <how-to-verify>
    Visit http://localhost:3000/feature and verify:
    1. [Visual check 1]
    2. [Visual check 2]
  </how-to-verify>
</task>
```

## CLI Installation Handling

**When a required CLI is not installed:**

| CLI | Auto-install? | Command |
|-----|---------------|---------|
| npm/pnpm/yarn | No - ask user | User chooses package manager |
| vercel | Yes | `npm i -g vercel` |
| gh (GitHub) | Yes | `brew install gh` (macOS) or `apt install gh` (Linux) |
| stripe | Yes | `npm i -g stripe` |
| supabase | Yes | `npm i -g supabase` |
| convex | No - use npx | `npx convex` (no install needed) |
| fly | Yes | `brew install flyctl` or curl installer |
| railway | Yes | `npm i -g @railway/cli` |

**Protocol:**
1. Try the command
2. If "command not found", check if auto-installable
3. If yes: install silently, retry command
4. If no: create checkpoint asking user to install

```xml
<!-- Example: vercel not found -->
<task type="auto">
  <name>Install Vercel CLI</name>
  <action>Run `npm i -g vercel`</action>
  <verify>`vercel --version` succeeds</verify>
  <done>Vercel CLI installed</done>
</task>
```

## Pre-Checkpoint Automation Failures

**When setup fails before checkpoint:**

| Failure | Response |
|---------|----------|
| Server won't start | Check error output, fix issue, retry (don't proceed to checkpoint) |
| Port in use | Kill stale process or use alternate port |
| Missing dependency | Run `npm install`, retry |
| Build error | Fix the error first (this is a bug, not a checkpoint issue) |
| Auth error | Create auth gate checkpoint |
| Network timeout | Retry with backoff, then checkpoint if persistent |

**Key principle:** Never present a checkpoint with broken verification environment. If `curl localhost:3000` fails, don't ask user to "visit localhost:3000".

```xml
<!-- WRONG: Checkpoint with broken environment -->
<task type="checkpoint:human-verify">
  <what-built>Dashboard (server failed to start)</what-built>
  <how-to-verify>Visit http://localhost:3000...</how-to-verify>
</task>

<!-- RIGHT: Fix first, then checkpoint -->
<task type="auto">
  <name>Fix server startup issue</name>
  <action>Investigate error, fix root cause, restart server</action>
  <verify>curl http://localhost:3000 returns 200</verify>
  <done>Server running correctly</done>
</task>

<task type="checkpoint:human-verify">
  <what-built>Dashboard - server running at http://localhost:3000</what-built>
  <how-to-verify>Visit http://localhost:3000/dashboard...</how-to-verify>
</task>
```

## Quick Reference

| Action | Automatable? | Claude does it? |
|--------|--------------|-----------------|
| Deploy to Vercel | Yes (`vercel`) | YES |
| Create Stripe webhook | Yes (API) | YES |
| Write .env file | Yes (Write tool) | YES |
| Create Upstash DB | Yes (`upstash`) | YES |
| Run tests | Yes (`npm test`) | YES |
| Start dev server | Yes (`npm run dev`) | YES |
| Add env vars to Convex | Yes (`npx convex env set`) | YES |
| Add env vars to Vercel | Yes (`vercel env add`) | YES |
| Seed database | Yes (CLI/API) | YES |
| Click email verification link | No | NO |
| Enter credit card with 3DS | No | NO |
| Complete OAuth in browser | No | NO |
| Visually verify UI looks correct | No | NO |
| Test interactive user flows | No | NO |

</automation_reference>

<writing_guidelines>

**DO:**
- Automate everything with CLI/API before checkpoint
- Be specific: "Visit https://myapp.vercel.app" not "check deployment"
- Number verification steps: easier to follow
- State expected outcomes: "You should see X"
- Provide context: why this checkpoint exists
- Make verification executable: clear, testable steps

**DON'T:**
- Ask human to do work Claude can automate (deploy, create resources, run builds)
- Assume knowledge: "Configure the usual settings" ❌
- Skip steps: "Set up database" ❌ (too vague)
- Mix multiple verifications in one checkpoint (split them)
- Make verification impossible (Claude can't check visual appearance without user confirmation)

**Placement:**
- **After automation completes** - not before Claude does the work
- **After UI buildout** - before declaring phase complete
- **Before dependent work** - decisions before implementation
- **At integration points** - after configuring external services

**Bad placement:**
- Before Claude automates (asking human to do automatable work) ❌
- Too frequent (every other task is a checkpoint) ❌
- Too late (checkpoint is last task, but earlier tasks needed its result) ❌
</writing_guidelines>

<examples>

### Example 1: Deployment Flow (Correct)

```xml
<!-- Claude automates everything -->
<task type="auto">
  <name>Deploy to Vercel</name>
  <files>.vercel/, vercel.json, package.json</files>
  <action>
    1. Run `vercel --yes` to create project and deploy
    2. Capture deployment URL from output
    3. Set environment variables with `vercel env add`
    4. Trigger production deployment with `vercel --prod`
  </action>
  <verify>
    - vercel ls shows deployment
    - curl {url} returns 200
    - Environment variables set correctly
  </verify>
  <done>App deployed to production, URL captured</done>
</task>

<!-- Human verifies visual/functional correctness -->
<task type="checkpoint:human-verify" gate="blocking">
  <what-built>Deployed to https://myapp.vercel.app</what-built>
  <how-to-verify>
    Visit https://myapp.vercel.app and confirm:
    - Homepage loads correctly
    - All images/assets load
    - Navigation works
    - No console errors
  </how-to-verify>
  <resume-signal>Type "approved" or describe issues</resume-signal>
</task>
```

### Example 2: Database Setup (No Checkpoint Needed)

```xml
<!-- Claude automates everything -->
<task type="auto">
  <name>Create Upstash Redis database</name>
  <files>.env</files>
  <action>
    1. Run `upstash redis create myapp-cache --region us-east-1`
    2. Capture connection URL from output
    3. Write to .env: UPSTASH_REDIS_URL={url}
    4. Verify connection with test command
  </action>
  <verify>
    - upstash redis list shows database
    - .env contains UPSTASH_REDIS_URL
    - Test connection succeeds
  </verify>
  <done>Redis database created and configured</done>
</task>

<!-- NO CHECKPOINT NEEDED - Claude automated everything and verified programmatically -->
```

### Example 3: Stripe Webhooks (Correct)

```xml
<!-- Claude automates everything -->
<task type="auto">
  <name>Configure Stripe webhooks</name>
  <files>.env, src/app/api/webhooks/route.ts</files>
  <action>
    1. Use Stripe API to create webhook endpoint pointing to /api/webhooks
    2. Subscribe to events: payment_intent.succeeded, customer.subscription.updated
    3. Save webhook signing secret to .env
    4. Implement webhook handler in route.ts
  </action>
  <verify>
    - Stripe API returns webhook endpoint ID
    - .env contains STRIPE_WEBHOOK_SECRET
    - curl webhook endpoint returns 200
  </verify>
  <done>Stripe webhooks configured and handler implemented</done>
</task>

<!-- Human verifies in Stripe dashboard -->
<task type="checkpoint:human-verify" gate="blocking">
  <what-built>Stripe webhook configured via API</what-built>
  <how-to-verify>
    Visit Stripe Dashboard > Developers > Webhooks
    Confirm: Endpoint shows https://myapp.com/api/webhooks with correct events
  </how-to-verify>
  <resume-signal>Type "yes" if correct</resume-signal>
</task>
```

### Example 4: Full Auth Flow Verification (Correct)

```xml
<task type="auto">
  <name>Create user schema</name>
  <files>src/db/schema.ts</files>
  <action>Define User, Session, Account tables with Drizzle ORM</action>
  <verify>npm run db:generate succeeds</verify>
</task>

<task type="auto">
  <name>Create auth API routes</name>
  <files>src/app/api/auth/[...nextauth]/route.ts</files>
  <action>Set up NextAuth with GitHub provider, JWT strategy</action>
  <verify>TypeScript compiles, no errors</verify>
</task>

<task type="auto">
  <name>Create login UI</name>
  <files>src/app/login/page.tsx, src/components/LoginButton.tsx</files>
  <action>Create login page with GitHub OAuth button</action>
  <verify>npm run build succeeds</verify>
</task>

<task type="auto">
  <name>Start dev server for auth testing</name>
  <action>Run `npm run dev` in background, wait for ready signal</action>
  <verify>curl http://localhost:3000 returns 200</verify>
  <done>Dev server running at http://localhost:3000</done>
</task>

<!-- ONE checkpoint at end verifies the complete flow - Claude already started server -->
<task type="checkpoint:human-verify" gate="blocking">
  <what-built>Complete authentication flow - dev server running at http://localhost:3000</what-built>
  <how-to-verify>
    1. Visit: http://localhost:3000/login
    2. Click "Sign in with GitHub"
    3. Complete GitHub OAuth flow
    4. Verify: Redirected to /dashboard, user name displayed
    5. Refresh page: Session persists
    6. Click logout: Session cleared
  </how-to-verify>
  <resume-signal>Type "approved" or describe issues</resume-signal>
</task>
```
</examples>

<anti_patterns>

### ❌ BAD: Asking user to start dev server

```xml
<task type="checkpoint:human-verify" gate="blocking">
  <what-built>Dashboard component</what-built>
  <how-to-verify>
    1. Run: npm run dev
    2. Visit: http://localhost:3000/dashboard
    3. Check layout is correct
  </how-to-verify>
</task>
```

**Why bad:** Claude can run `npm run dev`. User should only visit URLs, not execute commands.

### ✅ GOOD: Claude starts server, user visits

```xml
<task type="auto">
  <name>Start dev server</name>
  <action>Run `npm run dev` in background</action>
  <verify>curl localhost:3000 returns 200</verify>
</task>

<task type="checkpoint:human-verify" gate="blocking">
  <what-built>Dashboard at http://localhost:3000/dashboard (server running)</what-built>
  <how-to-verify>
    Visit http://localhost:3000/dashboard and verify:
    1. Layout matches design
    2. No console errors
  </how-to-verify>
</task>
```

### ❌ BAD: Asking user to add env vars in dashboard

```xml
<task type="checkpoint:human-action" gate="blocking">
  <action>Add environment variables to Convex</action>
  <instructions>
    1. Go to dashboard.convex.dev
    2. Select your project
    3. Navigate to Settings → Environment Variables
    4. Add OPENAI_API_KEY with your key
  </instructions>
</task>
```

**Why bad:** Convex has `npx convex env set`. Claude should ask for the key value, then run the CLI command.

### ✅ GOOD: Claude collects secret, adds via CLI

```xml
<task type="checkpoint:human-action" gate="blocking">
  <action>Provide your OpenAI API key</action>
  <instructions>
    I need your OpenAI API key. Get it from: https://platform.openai.com/api-keys
    Paste the key below (starts with sk-)
  </instructions>
  <verification>I'll configure it via CLI</verification>
  <resume-signal>Paste your key</resume-signal>
</task>

<task type="auto">
  <name>Add OpenAI key to Convex</name>
  <action>Run `npx convex env set OPENAI_API_KEY {key}`</action>
  <verify>`npx convex env get` shows OPENAI_API_KEY configured</verify>
</task>
```

### ❌ BAD: Asking human to deploy

```xml
<task type="checkpoint:human-action" gate="blocking">
  <action>Deploy to Vercel</action>
  <instructions>
    1. Visit vercel.com/new
    2. Import Git repository
    3. Click Deploy
    4. Copy deployment URL
  </instructions>
  <verification>Deployment exists</verification>
  <resume-signal>Paste URL</resume-signal>
</task>
```

**Why bad:** Vercel has a CLI. Claude should run `vercel --yes`.

### ✅ GOOD: Claude automates, human verifies

```xml
<task type="auto">
  <name>Deploy to Vercel</name>
  <action>Run `vercel --yes`. Capture URL.</action>
  <verify>vercel ls shows deployment, curl returns 200</verify>
</task>

<task type="checkpoint:human-verify">
  <what-built>Deployed to {url}</what-built>
  <how-to-verify>Visit {url}, check homepage loads</how-to-verify>
  <resume-signal>Type "approved"</resume-signal>
</task>
```

### ❌ BAD: Too many checkpoints

```xml
<task type="auto">Create schema</task>
<task type="checkpoint:human-verify">Check schema</task>
<task type="auto">Create API route</task>
<task type="checkpoint:human-verify">Check API</task>
<task type="auto">Create UI form</task>
<task type="checkpoint:human-verify">Check form</task>
```

**Why bad:** Verification fatigue. Combine into one checkpoint at end.

### ✅ GOOD: Single verification checkpoint

```xml
<task type="auto">Create schema</task>
<task type="auto">Create API route</task>
<task type="auto">Create UI form</task>

<task type="checkpoint:human-verify">
  <what-built>Complete auth flow (schema + API + UI)</what-built>
  <how-to-verify>Test full flow: register, login, access protected page</how-to-verify>
  <resume-signal>Type "approved"</resume-signal>
</task>
```

### ❌ BAD: Asking for automatable file operations

```xml
<task type="checkpoint:human-action">
  <action>Create .env file</action>
  <instructions>
    1. Create .env in project root
    2. Add: DATABASE_URL=...
    3. Add: STRIPE_KEY=...
  </instructions>
</task>
```

**Why bad:** Claude has Write tool. This should be `type="auto"`.

### ❌ BAD: Vague verification steps

```xml
<task type="checkpoint:human-verify">
  <what-built>Dashboard</what-built>
  <how-to-verify>Check it works</how-to-verify>
  <resume-signal>Continue</resume-signal>
</task>
```

**Why bad:** No specifics. User doesn't know what to test or what "works" means.

### ✅ GOOD: Specific verification steps (server already running)

```xml
<task type="checkpoint:human-verify">
  <what-built>Responsive dashboard - server running at http://localhost:3000</what-built>
  <how-to-verify>
    Visit http://localhost:3000/dashboard and verify:
    1. Desktop (>1024px): Sidebar visible, content area fills remaining space
    2. Tablet (768px): Sidebar collapses to icons
    3. Mobile (375px): Sidebar hidden, hamburger menu in header
    4. No horizontal scroll at any size
  </how-to-verify>
  <resume-signal>Type "approved" or describe layout issues</resume-signal>
</task>
```

### ❌ BAD: Asking user to run any CLI command

```xml
<task type="checkpoint:human-action">
  <action>Run database migrations</action>
  <instructions>
    1. Run: npx prisma migrate deploy
    2. Run: npx prisma db seed
    3. Verify tables exist
  </instructions>
</task>
```

**Why bad:** Claude can run these commands. User should never execute CLI commands.

### ❌ BAD: Asking user to copy values between services

```xml
<task type="checkpoint:human-action">
  <action>Configure webhook URL in Stripe</action>
  <instructions>
    1. Copy the deployment URL from terminal
    2. Go to Stripe Dashboard → Webhooks
    3. Add endpoint with URL + /api/webhooks
    4. Copy webhook signing secret
    5. Add to .env file
  </instructions>
</task>
```

**Why bad:** Stripe has an API. Claude should create the webhook via API and write to .env directly.

</anti_patterns>

<summary>

Checkpoints formalize human-in-the-loop points. Use them when Claude cannot complete a task autonomously OR when human verification is required for correctness.

**The golden rule:** If Claude CAN automate it, Claude MUST automate it.

**Checkpoint priority:**
1. **checkpoint:human-verify** (90% of checkpoints) - Claude automated everything, human confirms visual/functional correctness
2. **checkpoint:decision** (9% of checkpoints) - Human makes architectural/technology choices
3. **checkpoint:human-action** (1% of checkpoints) - Truly unavoidable manual steps with no API/CLI

**When NOT to use checkpoints:**
- Things Claude can verify programmatically (tests pass, build succeeds)
- File operations (Claude can read files to verify)
- Code correctness (use tests and static analysis)
- Anything automatable via CLI/API
</summary>