skill-coverage-audit

skill-coverage-audit is a skill for Claude Code from nyldn/claude-octopus. It costs 28 tokens per session (2,244 once invoked), scanned A, original, MIT.

A review of changed code that follows each execution path and compares those paths with the project’s tests.

In plain words
What is it for?
It helps audit test coverage, identify gaps, create tests for uncovered paths, and report the results.
Why use it?
It finds important branches that tests do not cover before changes are shipped.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter.

Part of the octo plugin — 70 skills, 106 commands, 10 agents, 18 hooks shipped together

Good fit It helps audit test coverage, identify gaps, create tests for uncovered paths, and report the results.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/nyldn/claude-octopus/skill-coverage-audit
About the project

Claude Octopus is an orchestration project that sends research, design, and coding tasks to Claude Code and other AI model providers so their results can be compared. Developers use it for multi-model work, disagreement detection, reviews, persistent context, and an optional workflow that moves from discovery through delivery. The catalogue entries are its commands, skills, agents, instructions, hooks, plugins, and settings.

nyldn/claude-octopus · 4,056 stars · on GitHub · reddit.com

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 nyldn/claude-octopus --skill skill-coverage-audit
Clone the repo
git clone --depth 1 https://github.com/nyldn/claude-octopus

Made for: Claude Code.

Or install octo, the plugin that ships this one along with the rest of its 70 skills, 106 commands, 10 agents, 18 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 skill-coverage-audit

README.md
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Your own site
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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.

agentmods 80×15 button for skill-coverage-audit

Your own site · 80×15
<a href="https://agentmods.dev/skills/nyldn/claude-octopus/skill-coverage-audit"><img src="https://agentmods.dev/badge/skills/nyldn/claude-octopus/skill-coverage-audit.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 28 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,244 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. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

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 →

  • medium Excessive Agency · line 250
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
How audits are shown
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 $0.00028 $0.02244
Opus 5 $0.00014 $0.01122
Sonnet 5 $0.00006 $0.00449
Haiku 4.5 $0.00003 $0.00224

Measured 9d ago against content hash 3533330f8482, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

skill-coverage-audit 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 9d 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.

.claude/skills/skill-coverage-audit/SKILL.md · 269 lines

How it starts

The opening of the file, as written. The whole thing — 269 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Test Coverage Audit

Overview

Trace every codepath in a diff, map each path against existing tests, visualize coverage gaps, and auto-generate tests for uncovered paths.

Core principle: Trace codepaths in changed files -> Map against existing tests -> Score coverage quality -> Generate tests for gaps -> Report before/after counts.


Caps and Limits

These hard limits prevent runaway analysis:

  • 30 code paths max per audit. If a diff yields more than 30, prioritize by complexity and risk (error paths, security-sensitive branches, public API surfaces first).
  • 20 tests generated max per audit. Focus on highest-impact gaps first.
  • 2-minute per-test exploration cap. If understanding a single test path takes longer than 2 minutes, mark it as "needs manual review" and move on.

Phase 1: Codepath Tracing

Step 1: Identify Changed Files

Determine the diff scope. Use the most relevant source:

# PR diff
git diff --name-only main...HEAD

# Staged changes
git diff --name-only --cached

# Last commit
git diff --name-only HEAD~1..HEAD

Filter to source code files only (exclude configs, docs, generated files).

Step 2: Trace Data Flow Through Every Branch

For each changed file, you MUST trace:

  1. Conditionals -- Every if/else, switch/case, ternary, and pattern match. Each branch is a separate codepath.
  2. Error paths -- Every catch, throw, error return, validation failure, and early return with error. WHY: Error paths are the most common source of untested bugs.
  3. Function calls -- Every function invoked from changed code. Trace one level deep into callees to identify integration boundaries.
  4. Loop boundaries -- Empty collection, single item, and multi-item paths through loops.
  5. Guard clauses -- Every early return, null check, and permission gate.

Step 3: Build the Codepath Inventory

Produce a structured inventory:

## Codepath Inventory: [filename]

| # | Path Description | Type | Risk |
|---|-----------------|------|------|
| 1 | validateUser() happy path | conditional | low |
| 2 | validateUser() missing email | error | medium |
| 3 | validateUser() invalid format | error | medium |
| 4 | processOrder() empty cart guard | guard | high |
| 5 | processOrder() payment timeout | error | high |
| 6 | processOrder() success | conditional | low |

Read the full file on GitHub · 269 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. 9d ago First seen · 269 lines · 28 tokens per session scan A 3533330f8482

Subscribe to this mod's changes

skill-coverage-audit is a skill published in the GitHub repository nyldn/claude-octopus (4,056 stars, last pushed today), licensed MIT. It adds 28 tokens to every session and 2,244 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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