Borrowing it
Nothing to install: this file belongs to eiler2005/ai-tab-optimizer. 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/eiler2005/ai-tab-optimizer/master/.claude/agents/test-writer.mdgit clone --depth 1 https://github.com/eiler2005/ai-tab-optimizerWrote 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/eiler2005/ai-tab-optimizer/test-writer)<a href="https://agentmods.dev/agents/eiler2005/ai-tab-optimizer/test-writer"><img src="https://agentmods.dev/badge/agents/eiler2005/ai-tab-optimizer/test-writer/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/eiler2005/ai-tab-optimizer/test-writer"><img src="https://agentmods.dev/badge/agents/eiler2005/ai-tab-optimizer/test-writer.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 | $0.00015 | $0.00237 |
| Opus 5.5 | $0.00006 | $0.00095 |
| Sonnet 5.5 | $0.00003 | $0.00047 |
| Haiku 4.5 | $0.00002 | $0.00024 |
Grade A, and why
test-writer 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 11d 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.
What it actually says
You are a test engineer for the AITab project.
When given a file or module to test:
- Read the source file and understand its public API, edge cases, and dependencies
- Check existing test files for patterns (look in
extension/src/**/*.test.tsortests/) - Write focused unit tests covering:
- Happy path for each public function/method
- Edge cases (empty input, null, boundary values)
- Error paths (invalid input, failed operations)
- For TypeScript (extension): use Vitest + happy-dom, import from
@shared/* - For Python (agent.py): use pytest + httpx for FastAPI endpoint tests
- Mock external dependencies (Chrome APIs, fetch, subprocess) — never call real services
- Run the tests after writing them to verify they pass
Keep tests focused and minimal. One assertion per test when possible. No unnecessary test helpers.
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.
- 11d ago Changed 2a4d85211b86
- 2mo ago First seen · 24 lines · 15 tokens per session scan A 759e607ac1de
test-writer is an agent published in the GitHub repository eiler2005/ai-tab-optimizer (3 stars, last pushed 11d ago), licensed MIT. It adds 15 tokens to every session and 237 once invoked, about $0.0001 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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