How do I install the AI Schema skill?

Run npx skillmds@latest add arcasilesgroup/ai-schema in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is AI Schema safe to use?

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Which AI agents work with AI Schema?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is AI Schema free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published AI Schema?

arcasilesgroup (@arcasilesgroup) published this skill. Their other Agent Skills are listed on their SkillMD profile.

AI Schema by arcasilesgroup — Agent Skill

Name: AI Schema
Author: arcasilesgroup

AI Schema

Designs schemas, plans safe migrations with rollback scripts, optimizes slow queries with index recommendations, defines data retention and GDPR right-to-erasure policies. Supports PostgreSQL, MySQL, SQLite, MongoDB. Trigger for 'add a column', 'we need a migration', 'the query is slow', 'define a retention policy', 'GDPR compliance for data'. Not for application-layer ORMs without DB schema; use /ai-code instead. Not for security audits; use /ai-security instead. Not for infrastructure provisioning — no infra skill exists.

File contents

Database Engineering

Schema design, safe migration generation, query optimization, and data lifecycle management across PostgreSQL, MySQL, SQLite, and MongoDB. Multi-ORM: SQLAlchemy, Prisma, TypeORM, Drizzle, Entity Framework, Diesel.

Process

Step 0 (load contexts): read .ai-engineering/manifest.yml providers.stacks; load .ai-engineering/overrides/<stack>/conventions.md for each stack and .ai-engineering/overrides/_shared/conventions.md; load .ai-engineering/team/*.md for team conventions.

Modes

design -- Schema Design

Analyze data model -- entities, relationships, access patterns, data volume, growth projections.
Apply normalization -- 3NF+ by default. Document denormalization decisions with rationale.
Design schema -- tables, indexes, constraints, partitioning for large tables.
Validate referential integrity -- every FK has a matching PK, cascade rules defined.
Output: DDL script + entity relationship description.

migrate -- Safe Migrations

Assess impact -- locking impact, backward compatibility, data volume affected.
Use expand-contract -- for breaking changes (add new, migrate data, drop old).
Generate forward migration -- with explicit transaction boundaries.
Generate rollback migration -- ALWAYS required. No migration ships without rollback.
Test migration -- verify on representative data volume.
Output: forward script, rollback script, execution plan.

optimize -- Query Optimization

Analyze execution plan -- EXPLAIN ANALYZE (PostgreSQL), EXPLAIN (MySQL).
Identify bottlenecks -- sequential scans, missing indexes, N+1 patterns.
Recommend indexes -- composite indexes based on query patterns, partial indexes for filtered queries.
Connection pool tuning -- pool size, timeout, idle connection management.
Output: optimized query, index recommendations, before/after execution plan.

lifecycle -- Data Lifecycle

Retention policies -- define per-table retention based on regulatory requirements.
Archival strategies -- partition-based archival, cold storage migration.
GDPR compliance -- right to erasure procedures, data anonymization.
Multi-DB architecture -- read replicas, caching layers, write distribution.
Output: lifecycle policy document, archival procedures.

Common Mistakes

Adding indexes without checking write impact -- indexes speed reads but slow writes.
Running DDL without --dry-run first -- destructive DDL requires explicit user approval.

Examples

Example — safe migration with backfill

User: "we need to add a soft-delete column to users with a backfill"

/ai-schema migrate

Generates up + down migration, default-backfill strategy, lock-impact analysis, rollback script, and a dry-run preview.

Integration

Calls: psql / mysql / sqlite3 / mongosh (verification). Triggers: /ai-security (injection pattern review). Integrates with: ORM migration systems (Alembic, Prisma Migrate, EF Migrations). See also: /ai-security, /ai-governance (destructive DDL approval).

References

.ai-engineering/manifest.yml -- governance rules for destructive operations.

$ARGUMENTS

---name: ai-schemadescription: Designs schemas, plans safe migrations with rollback scripts, optimizes slow queries with index recommendations, defines data retention and GDPR right-to-erasure policies. Supports PostgreSQL, MySQL, SQLite, MongoDB. Trigger for 'add a column', 'we need a migration', 'the query is slow', 'define a retention policy', 'GDPR compliance for data'. Not for application-layer ORMs without DB schema; use /ai-code instead. Not for security audits; use /ai-security instead. Not for infrastructure provisioning — no infra skill exists.---# Database EngineeringSchema design, safe migration generation, query optimization, and data lifecycle management across PostgreSQL, MySQL, SQLite, and MongoDB. Multi-ORM: SQLAlchemy, Prisma, TypeORM, Drizzle, Entity Framework, Diesel.## ProcessStep 0 (load contexts): read `.ai-engineering/manifest.yml` `providers.stacks`; load `.ai-engineering/overrides/<stack>/conventions.md` for each stack and `.ai-engineering/overrides/_shared/conventions.md`; load `.ai-engineering/team/*.md` for team conventions.## Modes### design -- Schema Design1. **Analyze data model** -- entities, relationships, access patterns, data volume, growth projections.2. **Apply normalization** -- 3NF+ by default. Document denormalization decisions with rationale.3. **Design schema** -- tables, indexes, constraints, partitioning for large tables.4. **Validate referential integrity** -- every FK has a matching PK, cascade rules defined.5. **Output**: DDL script + entity relationship description.### migrate -- Safe Migrations1. **Assess impact** -- locking impact, backward compatibility, data volume affected.2. **Use expand-contract** -- for breaking changes (add new, migrate data, drop old).3. **Generate forward migration** -- with explicit transaction boundaries.4. **Generate rollback migration** -- ALWAYS required. No migration ships without rollback.5. **Test migration** -- verify on representative data volume.6. **Output**: forward script, rollback script, execution plan.### optimize -- Query Optimization1. **Analyze execution plan** -- `EXPLAIN ANALYZE` (PostgreSQL), `EXPLAIN` (MySQL).2. **Identify bottlenecks** -- sequential scans, missing indexes, N+1 patterns.3. **Recommend indexes** -- composite indexes based on query patterns, partial indexes for filtered queries.4. **Connection pool tuning** -- pool size, timeout, idle connection management.5. **Output**: optimized query, index recommendations, before/after execution plan.### lifecycle -- Data Lifecycle1. **Retention policies** -- define per-table retention based on regulatory requirements.2. **Archival strategies** -- partition-based archival, cold storage migration.3. **GDPR compliance** -- right to erasure procedures, data anonymization.4. **Multi-DB architecture** -- read replicas, caching layers, write distribution.5. **Output**: lifecycle policy document, archival procedures.## Common Mistakes- Adding indexes without checking write impact -- indexes speed reads but slow writes.- Running DDL without `--dry-run` first -- destructive DDL requires explicit user approval.## Examples### Example — safe migration with backfillUser: "we need to add a soft-delete column to users with a backfill"```/ai-schema migrate```Generates up + down migration, default-backfill strategy, lock-impact analysis, rollback script, and a dry-run preview.## IntegrationCalls: `psql` / `mysql` / `sqlite3` / `mongosh` (verification). Triggers: `/ai-security` (injection pattern review). Integrates with: ORM migration systems (Alembic, Prisma Migrate, EF Migrations). See also: `/ai-security`, `/ai-governance` (destructive DDL approval).## References- `.ai-engineering/manifest.yml` -- governance rules for destructive operations.$ARGUMENTS

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