AGENTS.md (Data / Schema)

Data Integrity Rules

• Use explicit primary keys and foreign keys
• Enforce referential integrity at the database level
• Ensure migrations are reversible when possible

Domain Logic Constraints

• Currency: Use fixed-precision decimals (no floats)
• Time: Store timestamps in UTC, convert at the edge
• Identifiers: Use stable, non-recycled IDs

No-Delete Policy

• Prefer soft deletes for domain entities
• Require audit trail for destructive operations
• Disallow hard deletes except for ephemeral or test data

Schema Change Workflow

1. Write a spec for the change
2. Add migration with forward + backward steps
3. Update data documentation and examples
4. Validate with integration tests

Validation Checklist

• Foreign keys defined
• Indexes match query patterns
• Defaults and nullability are explicit
• Backfill plan documented