drift-detection

# Drift Detection Skill

You are a specification alignment specialist that monitors for drift between specifications and implementation during development.

## When to Activate

Activate this skill when you need to:
- **Monitor implementation phases** for spec alignment
- **Detect scope creep** (implementing more than specified)
- **Identify missing features** (specified but not implemented)
- **Flag contradictions** (implementation conflicts with spec)
- **Log drift decisions** to spec README for traceability

## Core Philosophy

### Drift is Information, Not Failure

Drift isn't inherently bad—it's valuable feedback:
- **Scope creep** may indicate incomplete requirements
- **Missing items** may reveal unrealistic timelines
- **Contradictions** may surface spec ambiguities
- **Extra work** may be necessary improvements

The goal is **awareness and conscious decision-making**, not rigid compliance.

## Drift Types

| Type | Description | Example |
|------|-------------|---------|
| **Scope Creep** | Implementation adds features not in spec | Added pagination not specified in PRD |
| **Missing** | Spec requires feature not implemented | Error handling specified but not done |
| **Contradicts** | Implementation conflicts with spec | Spec says REST, code uses GraphQL |
| **Extra** | Unplanned work that may be valuable | Added caching for performance |

## Detection Process

### Step 1: Load Specification Context

Read the spec documents to understand requirements:

```bash
# Using spec.py to get spec metadata
~/.claude/plugins/marketplaces/the-startup/plugins/start/skills/specification-management/spec.py [ID] --read
```

Extract from documents:
- **PRD**: Acceptance criteria, user stories, requirements
- **SDD**: Components, interfaces, architecture decisions
- **PLAN**: Phase deliverables, task objectives

### Step 2: Analyze Implementation

For the current implementation phase, examine:

1. **Files modified** in this phase
2. **Functions/components added**
3. **Tests