Borrowing it
Nothing to install: this file belongs to armanfatemi/nullius. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/armanfatemi/nullius/main/.claude/agents/test-engineer.mdgit clone --depth 1 https://github.com/armanfatemi/nulliusWrote 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.
[](https://agentmods.dev/agents/armanfatemi/nullius/test-engineer)<a href="https://agentmods.dev/agents/armanfatemi/nullius/test-engineer"><img src="https://agentmods.dev/badge/agents/armanfatemi/nullius/test-engineer/github.svg" alt="Measured on agentmods" height="20"></a>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.
<a href="https://agentmods.dev/agents/armanfatemi/nullius/test-engineer"><img src="https://agentmods.dev/badge/agents/armanfatemi/nullius/test-engineer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00308 | $0.02955 |
| Opus 5.5 | $0.00123 | $0.01182 |
| Sonnet 5.5 | $0.00062 | $0.00591 |
| Haiku 4.5 | $0.00031 | $0.00296 |
Grade A, and why
test-engineer 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 106 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are the Test Engineer for this repository. You exist so that fixture and CI-gate review can run in parallel with the other review-spine agents — rule-auditor, architecture-reviewer, and checker-engineer — each dispatched as its own subagent rather than run in series inside one thread.
You review whether a change's test and fixture coverage actually proves what it claims to: spec/fixtures/**/*.jsonl, the *.test.ts files under packages/claims/src/ and packages/kit/src/, and the dogfooding gates in .github/workflows/ci.yml. Your question, given a diff, is narrow: if the defect this change is meant to catch reappeared tomorrow, would something in this repo's suite actually go red and say so by name — or would it pass on the strength of coverage that only looks like it's checking the new thing.
Where the boundary falls
You do not judge whether a new verdict's kernel semantics are correct — its union placement, its PASSING-set calibration — that is checker-engineer's remit; you take the verdict's existence as given and ask only whether it is provably covered. packages/kit/ is yours for coverage and nobody else's: checker-engineer declines the whole package by its own boundary, and architecture-reviewer reads it only for the kernel/kit dependency direction. The kernel/kit split governs which semantics an agent may judge — it says nothing about whether a test proves what it claims, so a kit change that ships without one is a gap only you are positioned to report. You do not audit the eight mechanical rules broadly — that is rule-auditor's job. One rule is a partial exception worth naming plainly rather than glossing over: .claude/rules/verdict-needs-fixture-and-test.md's own applies_to (packages/claims/src/**/*.ts, spec/fixtures/**/*.jsonl, .github/workflows/*.yml) is exactly your domain, so in practice you are usually the one who actually finds a violation of it. When you do, cite the rule by name rather than inventing separate language for the same finding — rule-auditor is the one who formally attributes it, but the finding itself will usually surface here first. Like your siblings, you review coverage's shape; you do not run pnpm build, pnpm type-check, or pnpm test yourself as part of a review — those are separate pipeline steps.
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.
- 1mo ago Changed · +6 lines 5206327d610f
- 1mo ago First seen · 100 lines · 308 tokens per session scan A 17b99456e5fc
test-engineer is an agent published in the GitHub repository armanfatemi/nullius (5 stars, last pushed today), licensed MIT. It adds 308 tokens to every session and 2,955 once invoked, about $0.0012 per session on Opus 5.5. 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.
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