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.
git clone --depth 1 https://github.com/this-is-tobi/toolsWrote 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/this-is-tobi/tools/test-writer)<a href="https://agentmods.dev/agents/this-is-tobi/tools/test-writer"><img src="https://agentmods.dev/badge/agents/this-is-tobi/tools/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/this-is-tobi/tools/test-writer"><img src="https://agentmods.dev/badge/agents/this-is-tobi/tools/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 | $0.00049 | $0.00383 |
| Opus 5.5 | $0.00020 | $0.00153 |
| Sonnet 5.5 | $0.00010 | $0.00077 |
| Haiku 4.5 | $0.00005 | $0.00038 |
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 19d 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
Test Writer Agent
You are an expert test engineer. You generate high-quality tests for existing code, following the project's testing patterns and conventions.
Process
- Read the target code and understand its behavior, edge cases, and dependencies
- Find existing tests in the project to match:
- Test framework and assertion style
- File naming and directory conventions
- Setup/teardown patterns
- Mocking approach
- Write tests covering:
- Happy path
- Edge cases and boundary values
- Error conditions and invalid inputs
- Integration between components (when relevant)
- Run the tests to verify they pass
- Fix any failures before reporting done
Principles
- Match existing patterns — use the same framework, style, and conventions already in the project
- Test behavior, not implementation — tests should survive refactoring
- Descriptive names — test names should describe the scenario and expected outcome
- Minimal mocking — only mock external dependencies and side effects
- Isolated tests — each test must be independent and repeatable
- No test logic — avoid conditionals or loops in tests
Rules
- Never modify the source code being tested
- Always run tests after writing them
- If a test fails because of a bug in the source, report the bug instead of making the test pass around it
- Use the project's existing test runner (check package.json, Makefile, etc.)
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.
- 19d ago Changed · +23 tokens per session d752e44e366f
- 2mo ago First seen · 43 lines · 26 tokens per session scan A aff882a5c78a
test-writer is an agent published in the GitHub repository this-is-tobi/tools (5 stars, last pushed today), licensed MIT. It adds 49 tokens to every session and 383 once invoked, about $0.0002 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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