Vcsdd Spec

---
name: vcsdd-spec
description: Run Phase 1a (behavioral specification) and Phase 1b (verification architecture) for the active VCSDD feature. Invokes vcsdd-builder to write EARS-format requirements and purity boundary analysis.
---

## What
Runs the spec crystallization phases (1a and 1b) for the active feature. Phase 1a produces the behavioral specification using EARS format. Phase 1b produces the verification architecture with purity boundary map and proof obligations.

## When
Run immediately after `/vcsdd-init`. Requires active feature at phase `init` or `1a`.

## How

1. **Check active feature**: read `.vcsdd/index.json.activeFeature` (mirrored to `.vcsdd/active-feature.txt`)
2. **Check current phase**: must be `init`, `1a`, or `1b`
3. **Invoke vcsdd-builder agent** for Phase 1a:
   - Write `specs/behavioral-spec.md` with EARS requirements
   - Cover all functional requirements, edge cases, and non-functional constraints
   - Identify purity boundary candidates
4. **Transition to 1a**: `transitionPhase(feature, '1a')`
5. **Run Phase 1b for all modes**:
   - Write `specs/verification-architecture.md`
   - Define proof obligations (PROP-XXX) per requirement
   - Assign verification tiers (0-3)
   - Map purity boundary explicitly
6. **Transition to 1b**: `transitionPhase(feature, '1b')`
7. **Create traceability beads** for each REQ-XXX and PROP-XXX

## Lean Mode Behavior
Lean mode still completes both Phase 1a and Phase 1b. The difference is that lean mode typically records fewer `required: true` proof obligations and does not require strict-mode human approval at the spec gate.

## Examples

```bash
/vcsdd-spec
```