# Prompt: Cross-Document Consistency Analysis

Used in Finding #28.

## Setup

- Two documents provided as full text in a single prompt (~25KB total)
- Document A: `system-overview.md` (323 lines, narrative overview)
- Document B: `architecture.md` (213 lines, DDD-focused)
- No tools, no project context beyond the two documents
- Same prompt to all 3 models independently

## Prompt

```
You are analyzing two architecture documents that describe the SAME system.
Your task is to identify places where these documents CONTRADICT each other
— not where they differ in scope or detail level, but where they make
incompatible claims about the same concept.

## Categories of inconsistency to check:

1. **Terminology conflicts** — Same concept called different names in ways
   that imply different meanings (not just abbreviation)
2. **Structural contradictions** — Documents disagree about what is inside
   vs outside a component boundary
3. **Flow/sequence conflicts** — Documents describe incompatible orderings
   or data flows for the same process
4. **Ownership/authority conflicts** — Documents disagree about which
   component owns, writes, or is authoritative for a concept
5. **Philosophical contradictions** — Documents state incompatible
   foundational assumptions (e.g., event sourcing vs CRUD)

## What to EXCLUDE:

- Omissions (one doc covers something the other doesn't)
- Detail-level differences (one is more detailed than the other)
- Naming differences that are clearly just abbreviations
- Scope differences (one covers more topics)

## Output format per finding:

For each inconsistency found:
- **Category:** (one of the 5 above)
- **Severity:** Critical / High / Medium
- **Document A says:** (exact quote or precise paraphrase with section ref)
- **Document B says:** (exact quote or precise paraphrase with section ref)
- **Why these are incompatible:** (explain why both cannot be correct)
- **Impact:** (what would go wrong if an implementer followed both)

## Document A: [system-overview.md]

[FULL TEXT OF DOCUMENT A]

## Document B: [architecture.md]

[FULL TEXT OF DOCUMENT B]
```

## Key Design Decisions

1. **Explicit exclusion of omissions** — prevents models from padding
   findings with "Doc A mentions X but Doc B doesn't"
2. **Five specific categories** — focuses attention without being
   so restrictive that models miss novel inconsistency types
3. **Required "why incompatible" explanation** — forces models to reason
   about WHY differences matter, not just list differences
4. **Impact field** — grounds findings in practical consequences
5. **Both documents in single prompt** — enables cross-referencing
   without tool calls or context fragmentation

## Results

| Model | Time | Findings | Tokens/finding |
|-------|------|----------|----------------|
| Opus | 52s | 7 | 336 |
| GPT-5 | 125s | 6 | 2,967 |
| Sonnet | 14s | 4 | 194 |

Opus recommended for this task type.