authoring-requirements

# Authoring Requirements

## Purpose

Write technology-agnostic functional requirements, identify edge cases, and define measurable success criteria. Focus on WHAT the system does and WHY, never HOW it's implemented.

## Functional Requirements Format

Write requirements using the FR-XXX format with RFC 2119 keywords:

```markdown
## Functional Requirements

- **FR-001**: System MUST [specific capability]
- **FR-002**: Users MUST be able to [specific action]
- **FR-003**: System SHOULD [recommended behavior]
- **FR-004**: System MAY [optional capability]
```

### RFC 2119 Keywords

| Keyword | Meaning |
|---------|---------|
| **MUST** | Absolute requirement; no exceptions |
| **SHOULD** | Recommended; valid exceptions may exist |
| **MAY** | Optional; implementation choice |

See [RFC-2119-KEYWORDS.md](RFC-2119-KEYWORDS.md) for detailed usage guidance.

### FR Numbering Rules

1. Sequential numbering: FR-001, FR-002, FR-003...
2. No gaps in sequence
3. Three-digit padding (001, not 1)
4. Group related requirements together

### Writing Technology-Agnostic Requirements

**Good (what):**
- "System MUST notify users when their subscription expires"
- "Users MUST be able to export their data in a portable format"

**Bad (how):**
- "System MUST send email via SendGrid when subscription expires"
- "Users MUST be able to download a JSON export from the /api/export endpoint"

## Edge Cases

Identify 3-5 boundary conditions that need explicit handling:

```markdown
## Edge Cases

1. **System limits**: What happens at maximum capacity?
2. **Invalid input**: How are malformed requests handled?
3. **External failures**: What if dependencies are unavailable?
4. **Concurrent access**: How are race conditions prevented?
5. **Permission boundaries**: What happens with unauthorized access?
```

### Edge Case Categories

| Category | Examples |
|----------|----------|
| **System limits** | Max items, file size limits, rate limits |
| **Invalid input** | Empty fields, wrong types, bo