db-keys

db-keys is a skill for Claude Code from Hainrixz/claude-db. It costs 76 tokens per session (1,181 once invoked), scanned A, original, MIT.

A database review module for checking how tables identify their rows with primary keys. It examines missing keys, key choices, insert-order effects, and the risk of numeric identifiers running out.

In plain words
What is it for?
Use it to audit table schemas, compare natural keys with generated identifiers, review UUID and integer choices, and find primary-key problems before they affect growth.
Why use it?
Poor primary-key choices can make updates, replication, duplicate removal, and high-volume inserts less reliable or less efficient. The review highlights these design and scaling risks.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the claude-db plugin — 36 skills, 6 agents, 1 hook shipped together

Good fit Use it to audit table schemas, compare natural keys with generated identifiers, review UUID and integer choices, and find primary-key problems before they affect growth.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/hainrixz/claude-db/db-keys
Install

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.

Any agent
npx skills add Hainrixz/claude-db --skill db-keys
Clone the repo
git clone --depth 1 https://github.com/Hainrixz/claude-db

Made for: Claude Code.

Or install claude-db, the plugin that ships this one along with the rest of its 36 skills, 6 agents, 1 hook.

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.

agentmods badge for db-keys

README.md
[![agentmods](https://agentmods.dev/badge/skills/hainrixz/claude-db/db-keys.svg)](https://agentmods.dev/skills/hainrixz/claude-db/db-keys)
Your own site
<a href="https://agentmods.dev/skills/hainrixz/claude-db/db-keys"><img src="https://agentmods.dev/badge/skills/hainrixz/claude-db/db-keys.svg" alt="Measured on agentmods" height="20"></a>
Per session 76 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,181 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00076 $0.01181
Opus 5 $0.00038 $0.00590
Sonnet 5 $0.00015 $0.00236
Haiku 4.5 $0.00008 $0.00118

Measured 8d ago against content hash efd4dd5ec07b, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

db-keys 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 8d 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.

skills/db-keys/SKILL.md · 56 lines

How it starts

The opening of the file, as written. The whole thing — 56 lines — stays where its author put it; the contents beside it link to each section on GitHub.

db-keys (M2)

The primary key is the identity contract of a row: it dictates how the row is referenced, how it clusters on disk, and how it scales. A missing or exhausting PK is one of the few defects that can cap a score. This module is both-axis: identity/modeling on design, index locality and exhaustion on performance.

What it checks

  • No primary key (or no unique row identifier on a collection): the cap case. A table without a PK cannot be safely updated, replicated, or de-duplicated.
  • PK type strategy: random UUIDv4 as a clustered/leading B-tree key fragments inserts and bloats indexes; prefer time-ordered UUIDv7/ULID or bigint identity. Flag uuid_generate_v4() defaults on hot insert tables.
  • Postgres ≥18 (GA Sept 2025): native uuidv7() (RFC 9562) is the recommended time-ordered UUID PK default (timestamp recoverable via uuid_extract_timestamp()). When the detected engine is PG ≥18, treat a gen_random_uuid()/v4 default as a downgrade and recommend uuidv7(). Pre-18 or non-Postgres engines: gen_random_uuid() and app-side UUIDv7 remain fine.
  • Natural vs surrogate: a mutable natural key (email, slug) used as PK propagates churn through every FK; recommend a stable surrogate.
  • Integer width exhaustion: int4/serial/SERIAL PK on a table whose volume can exceed ~2.1B rows — int4 exhaustion is a production-halting event. bigint/bigserial is the safe default.
  • Composite PK ordering: when composite, the leading column should match the dominant access/partition pattern (ties to M9 tenant_id, M11 ESR).

Axis & severity

  • No PK on a relational/wide-column table: severity 5, fail, axis both, confidence established (caps both scores).
  • int4/serial PK near exhaustion: severity 5 only with Tier-1 row-count evidence; otherwise severity 4 warn, confidence directional (never caps without live data).
  • UUIDv4 clustered PK on a hot-insert table: severity 3, warn, axis performance, confidence directional.
  • Mutable natural-key PK: severity 3, warn, axis design.

Read the full file on GitHub · 56 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.

  1. 8d ago First seen · 56 lines · 76 tokens per session scan A efd4dd5ec07b

Subscribe to this mod's changes

db-keys is a skill published in the GitHub repository Hainrixz/claude-db (19 stars, last pushed 2mo ago), licensed MIT. It adds 76 tokens to every session and 1,181 once invoked, about $0.0004 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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