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 manhvann/codexkit --skill databasesgit clone --depth 1 https://github.com/manhvann/codexkitWrote 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/manhvann/codexkit/databases)<a href="https://agentmods.dev/skills/manhvann/codexkit/databases"><img src="https://agentmods.dev/badge/skills/manhvann/codexkit/databases/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/manhvann/codexkit/databases"><img src="https://agentmods.dev/badge/skills/manhvann/codexkit/databases.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00044 | $0.00811 |
| Opus 5.5 | $0.00018 | $0.00324 |
| Sonnet 5.5 | $0.00009 | $0.00162 |
| Haiku 4.5 | $0.00004 | $0.00081 |
Grade A, and why
ck:databases 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 1mo 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- ck:databases — 95% identical, 5 lines differ
How it starts
The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Databases Skill
Unified guide for working with MongoDB (document-oriented) and PostgreSQL (relational) databases. Choose the right database for your use case and master both systems.
When to Use This Skill
Use when:
- Designing database schemas and data models
- Writing queries (SQL or MongoDB query language)
- Building aggregation pipelines or complex joins
- Optimizing indexes and query performance
- Implementing database migrations
- Setting up replication, sharding, or clustering
- Configuring backups and disaster recovery
- Managing database users and permissions
- Analyzing slow queries and performance issues
- Administering production database deployments
Reference Navigation
Database Design
- db-design.md - Activate when user requests: Database/table design for transactional (OLTP), analytics (OLAP), create or extend schema, design fact/dimension tables, analyze/review CSV/JSON/SQL files to create tables, or need advice on data storage structure.
MongoDB References
- mongodb-crud.md - CRUD operations, query operators, atomic updates
- mongodb-aggregation.md - Aggregation pipeline, stages, operators, patterns
- mongodb-indexing.md - Index types, compound indexes, performance optimization
- mongodb-atlas.md - Atlas cloud setup, clusters, monitoring, search
PostgreSQL References
- postgresql-queries.md - SELECT, JOINs, subqueries, CTEs, window functions
- postgresql-psql-cli.md - psql commands, meta-commands, scripting
- postgresql-performance.md - EXPLAIN, query optimization, vacuum, indexes
- postgresql-administration.md - User management, backups, replication, maintenance
Python Utilities
Database utility scripts in scripts/:
- db_migrate.py - Generate and apply migrations for both databases (MongoDB and PostgreSQL)
- db_backup.py - Backup and restore MongoDB and PostgreSQL
- db_performance_check.py - Analyze slow queries and recommend indexes
What ships with it
25 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.
- analytics.md 5.3 KB
- db-design.md 6.3 KB
- incremental-etl.md 5.4 KB
- references/mongodb-aggregation.md 9.1 KB
- references/mongodb-atlas.md 9.1 KB
- references/mongodb-crud.md 8.2 KB
- references/mongodb-indexing.md 10 KB
- references/postgresql-administration.md 12 KB
- references/postgresql-performance.md 11 KB
- references/postgresql-psql-cli.md 10 KB
- references/postgresql-queries.md 9.9 KB
- scripts/db_backup.py 16 KB runs code
- scripts/db_migrate.py 14 KB runs code
- scripts/db_performance_check.py 16 KB runs code
- scripts/requirements.txt 558 B
- scripts/tests/requirements.txt 69 B
- scripts/tests/test_db_backup.py 11 KB runs code
- scripts/tests/test_db_migrate.py 9.3 KB runs code
- scripts/tests/test_db_performance_check.py 12 KB runs code
- stacks/bigquery.md 5.1 KB
- stacks/d1_cloudflare.md 3.4 KB
- stacks/mysql.md 5.5 KB
- stacks/postgres.md 5.8 KB
- stacks/sqlite.md 6.4 KB
- transactional.md 4.7 KB
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.
- 1mo ago First seen · 85 lines · 44 tokens per session scan A d543e65d6ba6
ck:databases is a skill published in the GitHub repository manhvann/codexkit (89 stars, last pushed 1mo ago), licensed MIT. It adds 44 tokens to every session and 811 once invoked, about $0.0002 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.
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