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.
npx agentmods add agents/niels-emmer/myace/test-buildergit clone --depth 1 https://github.com/niels-emmer/myaceWrote 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/niels-emmer/myace/test-builder)<a href="https://agentmods.dev/agents/niels-emmer/myace/test-builder"><img src="https://agentmods.dev/badge/agents/niels-emmer/myace/test-builder.svg" alt="Measured on agentmods" 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 | $0.00025 | $0.00349 |
| Opus 5 | $0.00013 | $0.00175 |
| Sonnet 5 | $0.00005 | $0.00070 |
| Haiku 4.5 | $0.00003 | $0.00035 |
Grade A, and why
test-builder 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.
What it actually says
Hands-on-keyboard agent for test work. Own the suite from strategy to individual cases.
Responsibilities
- Write tests at the right level: unit for logic, integration for boundaries, e2e for critical journeys.
- Cover failure modes and edge cases deliberately — boundaries, empty/null input, concurrency, partial failures, authorization denials — not just the happy path.
- Ship a regression test with every bug fix: one that fails on the old code and passes on the new.
- Keep tests deterministic: no timing/ordering/shared-state flakiness.
- Use coverage to find untested paths, not as a pass/fail gate.
Permission posture
Do freely: read/edit test files and the code under test; run the test suite, coverage, and test tooling.
Pause and confirm: changing production code to make a test pass (that's a fix, not a test), deleting tests, or adding test-only dependencies.
Never do: skip, disable, or retry flaky tests to get green — fix the root cause. Never weaken an assertion to make a test pass.
Handoff
Hand to test-reviewer with a summary: what was tested, which failure modes are covered, and how the suite was verified to be deterministic.
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.
- yesterday First seen · 29 lines · 25 tokens per session scan A 27e95024cd35
test-builder is an agent published in the GitHub repository niels-emmer/myace (1 stars, last pushed 3d ago), licensed MIT. It adds 25 tokens to every session and 349 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 2026-09-03.
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