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+---
+phase: 31
+slug: puter-js-zero-config-cloud
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-04-03
+---
+
+# Phase 31 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | vitest |
+| **Config file** | server/vitest.config.ts |
+| **Quick run command** | `cd /opt/nexus && pnpm --filter server test --run -- 31-puter` |
+| **Full suite command** | `cd /opt/nexus && pnpm --filter server test --run` |
+| **Estimated runtime** | ~15 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run quick command
+- **After every plan wave:** Run full suite command
+- **Before `/gsd:verify-work`:** Full suite must be green
+- **Max feedback latency:** 15 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 31-01-01 | 01 | 1 | CLOUD-01,02 | unit | `vitest run 31-puter` | ❌ W0 | ⬜ pending |
+| 31-01-02 | 01 | 1 | CLOUD-03 | unit | `vitest run 31-puter` | ❌ W0 | ⬜ pending |
+| 31-02-01 | 02 | 2 | CLOUD-03,04 | unit | `vitest run 31-google-oauth` | ❌ W0 | ⬜ pending |
+| 31-03-01 | 03 | 3 | CLOUD-04,05 | integration | `tsc --noEmit` | ✅ | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `server/src/__tests__/31-puter-proxy.test.ts` — stubs for CLOUD-01, CLOUD-02, CLOUD-03
+- [ ] `server/src/__tests__/31-google-oauth.test.ts` — stubs for CLOUD-03
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Puter auth popup opens and returns token | CLOUD-01 | Browser popup interaction | Click "Continue with Puter", verify popup opens, sign in, verify chat works |
+| Google OAuth PKCE completes | CLOUD-03 | Browser OAuth redirect | Click "Sign in with Google", complete OAuth, verify Gemini chat works |
+| Policy-risk note visible | CLOUD-03 | Visual verification | Verify warning about Google OAuth abuse detection is shown |
+| Cost tracking attribution | CLOUD-02 | End-to-end data flow | Send Puter message, check cost tracking view shows token counts |
+
+---
+
+## Validation Sign-Off
+
+- [ ] All tasks have `<automated>` verify or Wave 0 dependencies
+- [ ] Sampling continuity: no 3 consecutive tasks without automated verify
+- [ ] Wave 0 covers all MISSING references
+- [ ] No watch-mode flags
+- [ ] Feedback latency < 15s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending