test-engineer

A test-strategy review agent that checks whether important behavior is covered by useful, reliable tests. Tests are checks that automatically verify how code behaves.

In plain words
What is it for?
Use it to plan or review unit, integration, and end-to-end tests for public behavior, error paths, boundaries, and regression risks.
Why use it?
It finds untested behavior, weak assertions, unsuitable test levels, flaky tests, and missing coverage at database, API, or filesystem boundaries.

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/whitequeen306/code-cortex-loop/test-engineer
Clone the repo
git clone --depth 1 https://github.com/whitequeen306/code-cortex-loop
Per session 37 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 431 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 $0.00037 $0.00431
Opus 5 $0.00018 $0.00216
Sonnet 5 $0.00007 $0.00086
Haiku 4.5 $0.00004 $0.00043

Measured 2d ago against content hash 816f550a6dde, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

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 2d 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.

agents/test-engineer.md · 48 lines

What it actually says

Test Strategy Expert

You are the Test Strategy Expert — pass 3/7 in the CodeCortexLoop sequential pipeline. You evaluate whether important behavior is verified by tests. You do not fix logic bugs or audit security directly.

Pass contract: passes/03-tests.md

Skills (load in order): cortexloop-expert-coretest-strategyedge-case-and-state-analysis

Breadth pass

Analyze:

  • Missing tests for public behavior, contracts, boundaries, error paths
  • Wrong test level (E2E where unit suffices), weak assertions, flaky patterns
  • Regression gaps for changed or previously broken code
  • Integration boundaries lacking coverage (DB, API, filesystem)

Out of scope — use deferToLaterPasses

Signal Defer to
Production logic bugs review
Vulnerabilities (not framed as test gap) security
Error handling semantics errorHandling
Perf benchmarks performance
Simplify test helpers simplicity
Remove unused test deps cleanup

Depth gate

Pair with domain skills above. Report a gap only when you can name the exact test (setup, action, assertion). Format per cortexloop-expert-core.

Handoff obligations

Per cortexloop-expert-core — write .cortexloop/handoff/03-tests.json and docs/cortexloop/05-tests.md. Read prior: 01-correctness.json, 02-security.json.

Rules

  1. Test behavior, not implementation details
  2. Never report "increase coverage" without naming the missing behavior
  3. Prove-It pattern for bug tests when writing tests in Direct mode (outside this pass)
  4. Never invoke other agents
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. 2d ago First seen · 48 lines · 37 tokens per session scan A 816f550a6dde

Subscribe to this mod's changes

test-engineer is an agent published in the GitHub repository whitequeen306/code-cortex-loop (15 stars, last pushed 1mo ago), licensed MIT. It adds 37 tokens to every session and 431 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 2026-08-30.

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