Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add bugrabilge/bilge-development-kit --skill database-designgit clone --depth 1 https://github.com/bugrabilge/bilge-development-kitWrote 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.
[](https://agentmods.dev/skills/bugrabilge/bilge-development-kit/database-design)<a href="https://agentmods.dev/skills/bugrabilge/bilge-development-kit/database-design"><img src="https://agentmods.dev/badge/skills/bugrabilge/bilge-development-kit/database-design/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.
<a href="https://agentmods.dev/skills/bugrabilge/bilge-development-kit/database-design"><img src="https://agentmods.dev/badge/skills/bugrabilge/bilge-development-kit/database-design.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00036 | $0.01339 |
| Opus 5 | $0.00018 | $0.00669 |
| Sonnet 5 | $0.00007 | $0.00268 |
| Haiku 4.5 | $0.00004 | $0.00134 |
Grade A, and why
database-design 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 5d 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.
How it starts
The opening of the file, as written. The whole thing — 150 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Database Design
"Data is the foundation; a well-designed schema is the bedrock upon which reliable systems are built."
When to Use
- Designing new database schemas or tables
- Reviewing existing data models for normalization issues
- Planning indexing strategies for query performance
- Modeling relationships between entities
- Writing or reviewing migration scripts
- Choosing between SQL and NoSQL for a use case
- Optimizing slow queries through schema changes
Normalization Principles
First Normal Form (1NF)
- Every column contains atomic (indivisible) values
- No repeating groups or arrays stored in a single column
- Each row is uniquely identifiable via a primary key
Second Normal Form (2NF)
- Must satisfy 1NF
- Every non-key column depends on the entire primary key, not just part of it
- Eliminate partial dependencies in composite key tables
Third Normal Form (3NF)
- Must satisfy 2NF
- No transitive dependencies: non-key columns must not depend on other non-key columns
- Example violation: storing
cityandzip_codetogether when city is determined by zip
When to Denormalize
- Read-heavy workloads where join performance is critical
- Reporting tables and materialized views
- Caching layers (e.g., Redis-backed denormalized snapshots)
- Always document why denormalization was chosen and maintain consistency mechanisms
Primary Key Strategies
Auto-increment IDs
- Simple and sequential; good for internal-only references
- Can leak information about record count and creation rate
- Problematic in distributed systems (conflicts across nodes)
UUIDs (v4)
- Globally unique without coordination
- Poor index locality due to randomness (fragmented B-trees)
- Use UUIDv7 (time-ordered) for better index performance
ULIDs / Snowflake IDs
- Time-sortable and globally unique
- Better B-tree locality than UUIDv4
- Preferred for distributed systems needing ordered IDs
Natural Keys
- Use when a domain-meaningful unique value exists (e.g., ISO country codes)
- Immutable natural keys are safe; mutable ones cause cascading update pain
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.
- 5d ago First seen · 150 lines · 36 tokens per session scan A ba8c0db06395
database-design is a skill published in the GitHub repository bugrabilge/bilge-development-kit (10 stars, last pushed 4mo ago), licensed MIT. It adds 36 tokens to every session and 1,339 once invoked, about $0.0002 per session on Opus 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 2026-09-03.
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