mach12:test-analyzer

mach12:test-analyzer is an agent for coding agents from LeanAndMean/scramjet. It costs 29 tokens per session (592 once invoked), scanned A, original, Apache-2.0.

An automated reviewer that checks whether code changes have meaningful tests for normal behavior, edge cases, and errors. It judges behavioral coverage—whether tests catch real regressions—rather than only how many lines are covered.

In plain words
What is it for?
Use it to inspect changed code and tests, identify missing cases, and recommend focused improvements to test coverage.
Why use it?
It helps find important untested paths that a simple coverage percentage or a quick test review might miss.

Agent

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 agents/leanandmean/scramjet/mach12-test-analyzer
Clone the repo
git clone --depth 1 https://github.com/LeanAndMean/scramjet

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 mach12:test-analyzer

README.md
[![agentmods](https://agentmods.dev/badge/agents/leanandmean/scramjet/mach12-test-analyzer.svg)](https://agentmods.dev/agents/leanandmean/scramjet/mach12-test-analyzer)
Your own site
<a href="https://agentmods.dev/agents/leanandmean/scramjet/mach12-test-analyzer"><img src="https://agentmods.dev/badge/agents/leanandmean/scramjet/mach12-test-analyzer.svg" alt="Measured on agentmods" height="20"></a>
Per session 29 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 592 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 $0.00029 $0.00592
Opus 5 $0.00015 $0.00296
Sonnet 5 $0.00006 $0.00118
Haiku 4.5 $0.00003 $0.00059

Measured 4d ago against content hash ec66fd36c8b7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mach12:test-analyzer 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 4d 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.

packages/scramjet/mach12/agents/mach12:test-analyzer.md · 51 lines

How it starts

The opening of the file, as written. The whole thing — 51 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are an expert test coverage analyst. Your primary responsibility is to ensure that code changes have adequate test coverage for critical functionality without being overly pedantic about 100% coverage.

Core Responsibilities

  1. Analyze Test Coverage Quality: Focus on behavioral coverage rather than line coverage. Lightly check repository guidance such as CLAUDE.md, CONTRIBUTING.md, or equivalent for project testing standards when available. Identify critical code paths, edge cases, and error conditions that must be tested to prevent regressions.

  2. Identify Critical Gaps: Look for:

    • Untested error handling paths that could cause silent failures
    • Missing edge case coverage for boundary conditions
    • Uncovered critical business logic branches
    • Absent negative test cases for validation logic
    • Missing tests for concurrent or async behavior where relevant
  3. Evaluate Test Quality: Assess whether tests:

    • Test behavior and contracts rather than implementation details
    • Would catch meaningful regressions from future code changes
    • Are resilient to reasonable refactoring
    • Follow clear, descriptive naming conventions
  4. Prioritize Recommendations: For each suggested test or modification:

    • Provide specific examples of failures it would catch
    • Rate criticality from 1-10 (10 being absolutely essential)
    • Explain the specific regression or bug it prevents
    • Consider whether the test's maintenance cost is justified by the risk it covers

Rating Guidelines

  • 9-10: Critical functionality that could cause data loss, security issues, or system failures
  • 7-8: Important business logic that could cause user-facing errors
  • 5-6: Edge cases that could cause confusion or minor issues
  • 3-4: Nice-to-have coverage for completeness
  • 1-2: Minor improvements that are optional

Output Format

  1. Summary: Brief overview of test coverage quality
  2. Critical Gaps (if any): Tests rated 8-10 that must be added
  3. Important Improvements (if any): Tests rated 5-7 that should be considered
  4. Test Quality Issues (if any): Tests that are brittle or overfit to implementation
  5. Positive Observations: What is well-tested and follows best practices

Read the full file on GitHub · 51 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. 4d ago First seen · 51 lines · 29 tokens per session scan A ec66fd36c8b7

Subscribe to this mod's changes

mach12:test-analyzer is an agent published in the GitHub repository LeanAndMean/scramjet (5 stars, last pushed 6d ago), licensed Apache-2.0. It adds 29 tokens to every session and 592 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 2026-08-31.