| name | erd |
| description | Generate ERD .drawio — entities, attributes, 1-1/1-N/N-N relationships, PK/FK. Hand-authored XML with TechSphereX AI palette; complex SQL DDL → /diagram --from-sql. |
| user-invocable | true |
| argument-hint | <entity/relationship description> [--feature slug] [@schema.sql] |
/erd — Entity-Relationship Diagram (draw.io)
When to use
- Data model for design docs / BA–dev alignment
- A few–dozens of entities described in words (no SQL importer needed)
- Need a hand-editable
.drawio file
Switch to /diagram when: large SQL DDL file (sqlerd.py), auto-layout for dozens of tables, or batch PNG export.
Input examples
/erd Order 1-N OrderLine, Order N-1 Customer, Order 1-1 Payment --feature booking
/erd auth module: User, Role, UserRole (N-N), Permission
/erd @schema.sql → suggest /diagram --from-sql if >8 tables
Workflow
Phase 1 — Inventory
List:
| Entity | PK | Attributes (short) | Notes |
|---|
| | | |
Relationships: A 1—N B, A N—N B (// associative entity if needed).
Missing relationship names / cardinality → ask 1–2 questions; do not invent FKs.
Phase 2 — L3 layout preview
Node + edge table (ASCII/table). User reviews before XML.
Phase 3 — Generate XML
Use @_templates/erd.drawio as the frame:
- Entity = rounded rect (or swimlane-style header): bold entity name + attr list
- Mark PK as
PK; FK as FK (text only)
- Edge:
endArrow=ERoneToMany / ERmandOne / ERzeroToMany when appropriate; fallback endArrow=block + labels 1 / N on the edge
- Palette: entity fill
#dae8fc, associative #fff2cc, external ref #f5f5f5 (per conventions)
- Grid 20; entity box ~200×(40 + 20×attr count)
Phase 4 — L1 → Write
docs/diagrams/{feature}/erd-{slug}.drawio
Mandatory rules
- @.claude/rules/drawio-conventions.md (core shapes, escape XML)
- @.claude/rules/naming-conventions.md
- @.claude/rules/approval-gate.md
- Do not invent columns/relationships; TBD + ask
- ≤ 15 entities per page — more: split by domain or use
/diagram + sqlerd/autolayout
Output
docs/diagrams/{feature}/erd-{slug}.drawio
References
- @_templates/erd.drawio
- @.claude/rules/drawio-conventions.md
- Advanced: skill
/diagram + scripts/sqlerd.py
