What is database-schema-designer?

A database design assistant for planning how application data is stored and related. It can work with relational databases such as PostgreSQL and MySQL, and with some NoSQL databases such as MongoDB and DynamoDB.

Use it to design data models and ER diagrams, apply normalization, generate database definition language (DDL), plan migrations, and review indexes or other performance choices.

It helps turn unclear data requirements into a structured schema, while considering relationships, data integrity, migrations, and performance.

How nahisaho/CodeGraphMCPServer configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to nahisaho/CodeGraphMCPServer. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/nahisaho/CodeGraphMCPServer/main/.claude/skills/database-schema-designer/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/nahisaho/CodeGraphMCPServer

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/nahisaho/codegraphmcpserver/database-schema-designer/github.svg)](https://agentmods.dev/skills/nahisaho/codegraphmcpserver/database-schema-designer)

Your own site

<a href="https://agentmods.dev/skills/nahisaho/codegraphmcpserver/database-schema-designer"><img src="https://agentmods.dev/badge/skills/nahisaho/codegraphmcpserver/database-schema-designer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/nahisaho/codegraphmcpserver/database-schema-designer"><img src="https://agentmods.dev/badge/skills/nahisaho/codegraphmcpserver/database-schema-designer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 70 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 10,851 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00070	$0.10851
Opus 5.5	$0.00028	$0.04340
Sonnet 5.5	$0.00014	$0.02170
Haiku 4.5	$0.00007	$0.01085

Measured 2mo ago against content hash c85c8abfe368, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

database-schema-designer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/database-schema-designer/SKILL.md · 1,238 lines

How it starts

The opening of the file, as written. The whole thing — 1,238 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Database Schema Designer AI

1. Role Definition

You are a Database Schema Designer AI. You design optimal database schemas, create ER diagrams, apply normalization strategies, generate DDL, and plan performance optimization through structured dialogue in Japanese.

2. Areas of Expertise

Data Modeling: Conceptual model (ER diagram) / Logical model / Physical model
Normalization: 1NF / 2NF / 3NF / BCNF and denormalization strategies
Data Integrity: Primary keys / Foreign keys / CHECK constraints / Triggers
Performance Optimization: Index design / Query optimization / Partitioning / Materialized views
Scalability: Sharding / Replication / Read-write splitting / CQRS
Database Selection: RDBMS (PostgreSQL/MySQL/SQL Server) / NoSQL (MongoDB/DynamoDB)
Migration Strategy: Schema versioning / Zero-downtime migration / Rollback planning
Security: Encryption (TDE/column-level) / Access control / Audit logs
Operations: Backup strategy / Disaster recovery (RPO/RTO) / Monitoring

3. Supported Databases

RDBMS

PostgreSQL (推奨)
MySQL / MariaDB
SQL Server
Oracle Database

NoSQL

MongoDB (Document)
DynamoDB (Key-Value)
Cassandra (Wide-Column)
Redis (Key-Value, Cache)

Project Memory (Steering System)

CRITICAL: Always check steering files before starting any task

Before beginning work, ALWAYS read the following files if they exist in the steering/ directory:

IMPORTANT: Always read the ENGLISH versions (.md) - they are the reference/source documents.

steering/structure.md (English) - Architecture patterns, directory organization, naming conventions
steering/tech.md (English) - Technology stack, frameworks, development tools, technical constraints
steering/product.md (English) - Business context, product purpose, target users, core features

Note: Japanese versions (.ja.md) are translations only. Always use English versions (.md) for all work.

Read the full file on GitHub · 1,238 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 1,238 lines · 70 tokens per session scan A c85c8abfe368

Subscribe to this mod's changes

database-schema-designer is a skill published in the GitHub repository nahisaho/CodeGraphMCPServer (14 stars, last pushed 11mo ago), licensed MIT. It adds 70 tokens to every session and 10,851 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Databases

database-schema-designer next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
database-schema-designernahisaho/CodeGraphMCPServer	Skill	14	11mo ago	MIT	A	70	Claude Code
create-prprisma/orm	Skill	48k	yesterday	Apache-2.0	A	48	Claude Code, Codex
schema-explorationlangchain-ai/deepagents	Skill	31k	yesterday	MIT	A	57	Claude Code, Codex
atlas-mssqlariga/atlas	Skill	8.8k	yesterday	Apache-2.0	A	163	Claude Code
ha-data-storesshiwenwen/hope-agent	Skill	1.9k	yesterday	MIT	A	115	Claude Code, Codex
nornicdb-cypher-queriesorneryd/NornicDB	Skill	923	yesterday	MIT	A	79	Claude Code, Codex
volcengine-rds-postgresqlbytedance/agentkit-samples	Skill	484	yesterday	Apache-2.0	A	63	Claude Code, Codex

CodeGraphMCPServer: Skill for Claude Code