# Mapping Specificity Rule: Broad vs Narrow vs Exact Mappings

## 🚨 CRITICAL: Mapping Semantics

When mapping LinkML classes to external ontologies, you MUST distinguish between **equivalence**, **hypernyms** (broader concepts), and **hyponyms** (narrower concepts).

### The Rule

1.  **Exact Mappings (`skos:exactMatch`)**: Use ONLY when the external concept is **semantically equivalent** to your class.
    *   *Example*: `hc:Person` `exact_mappings` `schema:Person`.

2.  **Broad Mappings (`skos:broadMatch`)**: Use when the external concept is a **hypernym** (a broader, more general category) of your class.
    *   *Example*: `hc:AcademicArchiveRecordSetType` `broad_mappings` `rico:RecordSetType`.
    *   *Rationale*: An academic archive record set *is a* record set type, but `rico:RecordSetType` is broader.
    *   *Common Hypernyms*: `skos:Concept`, `prov:Entity`, `schema:Thing`, `schema:Organization`, `rico:RecordSetType`.

3.  **Narrow Mappings (`skos:narrowMatch`)**: Use when the external concept is a **hyponym** (a narrower, more specific category) of your class.
    *   *Example*: `hc:Organization` `narrow_mappings` `hc:Library` (if mapping inversely).

### Common Violations to Avoid

❌ **WRONG**:
```yaml
AcademicArchiveRecordSetType:
  exact_mappings:
    - rico:RecordSetType  # WRONG: This implies AcademicArchiveRecordSetType == RecordSetType
```

✅ **CORRECT**:
```yaml
AcademicArchiveRecordSetType:
  broad_mappings:
    - rico:RecordSetType  # CORRECT: RecordSetType is broader
```

❌ **WRONG**:
```yaml
SocialMovement:
  exact_mappings:
    - schema:Organization # WRONG: SocialMovement is a specific TYPE of Organization
```

✅ **CORRECT**:
```yaml
SocialMovement:
  broad_mappings:
    - schema:Organization # CORRECT
```

### Verification Checklist

- [ ] Does the `exact_mapping` represent the **exact same scope**?
- [ ] If the external term is a generic parent class (e.g., `Type`, `Concept`, `Entity`), move it to `broad_mappings`.
- [ ] If the external term is a specific instance or subclass, check `narrow_mappings`.