#region FeatureSpec [C:3] [TYPE ADR] [SEMANTICS spec,requirements,feature]
@BRIEF Feature specification — WHAT the user needs and WHY. Implementation-free. Survives HCA 128× via @SEMANTICS grouping.

## Navigation (DSA Indexer keywords)
@SEMANTICS: spec, requirements, feature, [DOMAIN_KEYWORD_1], [DOMAIN_KEYWORD_2]

**Feature Branch**: `[###-feature-name]`  
**Created**: [DATE] | **Status**: Draft  
**Input**: "$ARGUMENTS"

## User Scenarios

Each story is an independently testable unit. Prioritized P1 (MVP) → P2 → P3.
All stories share `@SEMANTICS` domain keywords from the feature header.

### Story 1 — [Brief Title] (P1)

**Why P1**: [One sentence — value delivered]

**Independent Test**: [One sentence — how to verify this story alone]

**Acceptance**:
1. **Given** [state] **When** [action] **Then** [outcome]
2. **Given** [state] **When** [action] **Then** [outcome]

---

### Story 2 — [Brief Title] (P2)

**Why P2**: [One sentence]

**Independent Test**: [One sentence]

**Acceptance**:
1. **Given** [state] **When** [action] **Then** [outcome]

---

### Story 3 — [Brief Title] (P3)

**Why P3**: [One sentence]

**Independent Test**: [One sentence]

**Acceptance**:
1. **Given** [state] **When** [action] **Then** [outcome]

---

### Edge Cases
- [boundary condition] → [expected behavior]
- [error scenario] → [expected recovery]
- [empty/null state] → [expected fallback]

## Requirements

### Functional (IDs survive HCA 128× via hierarchical naming)

- **[DOMAIN]-FR-001**: [specific capability]
- **[DOMAIN]-FR-002**: [specific capability]
- **[DOMAIN]-FR-003**: [key interaction]
- **[DOMAIN]-FR-004**: [data requirement]
- **[DOMAIN]-FR-005**: [behavior requirement]

*Unclear requirements use:* `[NEEDS CLARIFICATION: topic]` — maximum 3 markers.

### Key Entities

- **[Entity]**: [What it represents, key attributes without implementation]
- **[Entity]**: [What it represents, relationships to other entities]

## Success Criteria

- **SC-001**: [Measurable metric — time, throughput, percentage]
- **SC-002**: [Measurable metric]
- **SC-003**: [User-facing metric]

#endregion FeatureSpec