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+---
+phase: 1
+slug: tradier-data-layer
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-03-29
+---
+
+# Phase 1 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | pytest 7.x |
+| **Config file** | none — Wave 0 installs |
+| **Quick run command** | `python -m pytest tests/test_tradier.py -x -q` |
+| **Full suite command** | `python -m pytest tests/ -q` |
+| **Estimated runtime** | ~5 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `python -m pytest tests/test_tradier.py -x -q`
+- **After every plan wave:** Run `python -m pytest tests/ -q`
+- **Before `/gsd:verify-work`:** Full suite must be green
+- **Max feedback latency:** 5 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| TBD | TBD | TBD | DATA-01 | unit | `python -m pytest tests/test_tradier.py -k chain -q` | ❌ W0 | ⬜ pending |
+| TBD | TBD | TBD | DATA-02 | unit | `python -m pytest tests/test_tradier.py -k expirations -q` | ❌ W0 | ⬜ pending |
+| TBD | TBD | TBD | DATA-03 | unit | `python -m pytest tests/test_tradier.py -k greeks -q` | ❌ W0 | ⬜ pending |
+| TBD | TBD | TBD | DATA-04 | unit | `python -m pytest tests/test_tradier.py -k iv -q` | ❌ W0 | ⬜ pending |
+| TBD | TBD | TBD | DATA-05 | unit | `python -m pytest tests/test_tradier.py -k dte -q` | ❌ W0 | ⬜ pending |
+| TBD | TBD | TBD | DATA-08 | integration | `python -m pytest tests/test_tradier.py -k vendor -q` | ❌ W0 | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `tests/test_tradier.py` — stubs for DATA-01 through DATA-05 and DATA-08
+- [ ] `tests/conftest.py` — shared fixtures (mock Tradier responses)
+- [ ] pytest install — if not already present
+
+*If none: "Existing infrastructure covers all phase requirements."*
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Production Greeks accuracy | DATA-03 | Sandbox returns no Greeks; production API key required | Call chain for AAPL, verify delta/gamma/theta/vega/rho are non-null floats |
+
+---
+
+## 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 < 5s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending