rb:constraint-debug

rb:constraint-debug is a skill for Claude Code, Codex from slbug/claude-ruby-grape-rails. It costs 44 tokens per session (159 once invoked), scanned A, original, MIT.

A debugger for database constraint failures such as duplicate values, missing required fields, and references to nonexistent records.

In plain words
What is it for?
It is for investigating unique-index, foreign-key, and NOT-NULL errors, including race conditions, transactions, locks, and migrations.
Why use it?
It compares application behavior with the database's actual rules, helping explain why a write was rejected.

Skill for Claude CodeCodex

Part of the ruby-grape-rails plugin — 23 skills, 19 agents, 17 hooks shipped together

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.

agentmods
npx agentmods add skills/slbug/claude-ruby-grape-rails/active-record-constraint-debug
Any agent
npx skills add slbug/claude-ruby-grape-rails --skill active-record-constraint-debug
Clone the repo
git clone --depth 1 https://github.com/slbug/claude-ruby-grape-rails

Made for: Claude Code, Codex.

Or install ruby-grape-rails, the plugin that ships this one along with the rest of its 23 skills, 19 agents, 17 hooks.

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 rb:constraint-debug

README.md
[![agentmods](https://agentmods.dev/badge/skills/slbug/claude-ruby-grape-rails/active-record-constraint-debug.svg)](https://agentmods.dev/skills/slbug/claude-ruby-grape-rails/active-record-constraint-debug)
Your own site
<a href="https://agentmods.dev/skills/slbug/claude-ruby-grape-rails/active-record-constraint-debug"><img src="https://agentmods.dev/badge/skills/slbug/claude-ruby-grape-rails/active-record-constraint-debug.svg" alt="Measured on agentmods" height="20"></a>
Per session 44 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 159 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00044 $0.00159
Opus 5 $0.00022 $0.00079
Sonnet 5 $0.00009 $0.00032
Haiku 4.5 $0.00004 $0.00016

Measured 3d ago against content hash a65c4c3df6eb, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

rb:constraint-debug 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.

plugins/ruby-grape-rails/skills/active-record-constraint-debug/SKILL.md · 21 lines

What it actually says

Constraint Debug

Check:

  • the actual database constraint or index definition
  • whether application validation matches database truth
  • whether the failing write should be wrapped in a transaction or lock
  • whether stale data or a bad migration introduced the mismatch

References

Need Reference
race-condition upserts, FK violations, check-constraint debugging recipes ${CLAUDE_SKILL_DIR}/references/constraint-patterns.md
Files

What ships with it

1 file 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.

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. 3d ago First seen · 21 lines · 44 tokens per session scan A a65c4c3df6eb

Subscribe to this mod's changes

rb:constraint-debug is a skill published in the GitHub repository slbug/claude-ruby-grape-rails (7 stars, last pushed 4d ago), licensed MIT. It adds 44 tokens to every session and 159 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 2026-08-31.