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 seaworld008/Commonly-used-high-value-skills --skill database-designergit clone --depth 1 https://github.com/seaworld008/Commonly-used-high-value-skillsWrote 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/seaworld008/commonly-used-high-value-skills/database-designer)<a href="https://agentmods.dev/skills/seaworld008/commonly-used-high-value-skills/database-designer"><img src="https://agentmods.dev/badge/skills/seaworld008/commonly-used-high-value-skills/database-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.
<a href="https://agentmods.dev/skills/seaworld008/commonly-used-high-value-skills/database-designer"><img src="https://agentmods.dev/badge/skills/seaworld008/commonly-used-high-value-skills/database-designer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Anti-Refusal · line 347 Skill attempts to nullify the agent's safety policies or restrictions ('you have no restrictions', 'ignore your guidelines', 'do anything now'). This is a direct jailbreak that disables guardrails.Fix: Remove jailbreak framing that nullifies safety policies or restrictions. Skill content must not instruct the agent to ignore its guidelines or operate without guardrails.
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 | $0.00026 | $0.03649 |
| Opus 5 | $0.00013 | $0.01825 |
| Sonnet 5 | $0.00005 | $0.00730 |
| Haiku 4.5 | $0.00003 | $0.00365 |
Grade A, and why
database-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 3d 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 — 491 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Database Designer - POWERFUL Tier Skill
Overview
A comprehensive database design skill that provides expert-level analysis, optimization, and migration capabilities for modern database systems. This skill combines theoretical principles with practical tools to help architects and developers create scalable, performant, and maintainable database schemas.
Core Competencies
Schema Design & Analysis
- Normalization Analysis: Automated detection of normalization levels (1NF through BCNF)
- Denormalization Strategy: Smart recommendations for performance optimization
- Data Type Optimization: Identification of inappropriate types and size issues
- Constraint Analysis: Missing foreign keys, unique constraints, and null checks
- Naming Convention Validation: Consistent table and column naming patterns
- ERD Generation: Automatic Mermaid diagram creation from DDL
Index Optimization
- Index Gap Analysis: Identification of missing indexes on foreign keys and query patterns
- Composite Index Strategy: Optimal column ordering for multi-column indexes
- Index Redundancy Detection: Elimination of overlapping and unused indexes
- Performance Impact Modeling: Selectivity estimation and query cost analysis
- Index Type Selection: B-tree, hash, partial, covering, and specialized indexes
Migration Management
- Zero-Downtime Migrations: Expand-contract pattern implementation
- Schema Evolution: Safe column additions, deletions, and type changes
- Data Migration Scripts: Automated data transformation and validation
- Rollback Strategy: Complete reversal capabilities with validation
- Execution Planning: Ordered migration steps with dependency resolution
Database Design Principles
Normalization Forms
First Normal Form (1NF)
- Atomic Values: Each column contains indivisible values
- Unique Column Names: No duplicate column names within a table
- Uniform Data Types: Each column contains the same type of data
- Row Uniqueness: No duplicate rows in the table
What ships with it
14 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- assets/sample_query_patterns.json 9.0 KB
- assets/sample_schema.json 9.1 KB
- assets/sample_schema.sql 8.1 KB
- expected_outputs/index_optimization_sample.txt 2.6 KB
- expected_outputs/migration_sample.txt 4.4 KB
- expected_outputs/schema_analysis_sample.txt 7.3 KB
- EXTENDED.md 2.0 KB
- index_optimizer.py 38 KB runs code
- migration_generator.py 49 KB runs code
- README.md 12 KB
- references/database_selection_decision_tree.md 16 KB
- references/index_strategy_patterns.md 12 KB
- references/normalization_guide.md 10 KB
- schema_analyzer.py 41 KB runs code
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.
- 3d ago Changed · -58 lines · -23 tokens per session 62154d7cfec6
- 11d ago First seen · 549 lines · 49 tokens per session scan A 3407b5f86dfd
database-designer is a skill published in the GitHub repository seaworld008/Commonly-used-high-value-skills (70 stars, last pushed 4d ago), licensed MIT. It adds 26 tokens to every session and 3,649 once invoked, about $0.0001 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 2026-08-30.
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