coalmine

A collection of nine code-quality review skills for coding agents. It audits areas such as code health, completeness, source accuracy, dependencies, failure handling, logging, testability, performance, and changes between schemas or contracts.

In plain words
What is it for?
Use it for code-health reviews, completeness checks, source-grounding checks, dependency and build audits, failure analysis, observability reviews, testability audits, scaling reviews, and contract-drift checks.
Why use it?
It helps reveal quality risks and missing safeguards across a project. The reviews produce findings and reports rather than automatically changing the code.

Plugin for Claude Code

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.

Claude Code
/plugin marketplace add HetCreep/CoalMine
agentmods
npx agentmods add plugins/hetcreep/coalmine/plugin
Clone the repo
git clone --depth 1 https://github.com/HetCreep/CoalMine

Made for: Claude Code.

Per session not measured What this adds to a session before it is invoked.
When invoked not measured Not applicable: nothing here is loaded into a session.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod in the catalogue.
Security

Grade A, and why

coalmine 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 yesterday.

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.

Origin

This is a copy

100% identical to coalmine — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugin/.claude-plugin/plugin.json · 28 lines

What it actually says

{
  "name": "coalmine",
  "version": "3.18.1",
  "description": "CoalMine — 9 quality-canary skills for coding agents: rot-canary (code-health audit + auto-cadence hooks), gold-standard (world-class completeness; fills & adopts rules), source-grounding (anti-hallucination sourcing), supply-chain-audit (deps/build/artifact trust), resilience-audit (failure-mode FMEA), telemetry-canary (observability/logging), testability-canary (decoupling/DI), scale-canary (perf scaling), drift-canary (contract/schema drift). Sub-agent + model-aware, cross-platform, report-not-fix.",
  "author": {
    "name": "HetCreep"
  },
  "homepage": "https://github.com/HetCreep/CoalMine",
  "repository": "https://github.com/HetCreep/CoalMine",
  "license": "Apache-2.0",
  "keywords": [
    "code-review",
    "code-health",
    "quality",
    "audit",
    "dead-code",
    "supply-chain",
    "resilience",
    "hallucination",
    "observability",
    "testability",
    "performance",
    "drift",
    "skills",
    "hooks"
  ]
}
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. yesterday First seen · 28 lines scan A 855ffe730ae4

Subscribe to this mod's changes

coalmine is a plugin published in the GitHub repository HetCreep/CoalMine (12 stars, last pushed 7d ago), licensed Apache-2.0. Its token cost is not measured: this kind of file is read by the harness, not the model. A static security scan graded it A with 0 findings. It is 100% identical to coalmine, differing in 0 lines, and is treated as a copy.