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/mordilion/ai-instructions-and-promptsWrote 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/mordilion/ai-instructions-and-prompts/test-writer)<a href="https://agentmods.dev/agents/mordilion/ai-instructions-and-prompts/test-writer"><img src="https://agentmods.dev/badge/agents/mordilion/ai-instructions-and-prompts/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/mordilion/ai-instructions-and-prompts/test-writer"><img src="https://agentmods.dev/badge/agents/mordilion/ai-instructions-and-prompts/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 | $0.00028 | $0.00175 |
| Opus 5 | $0.00014 | $0.00088 |
| Sonnet 5 | $0.00006 | $0.00035 |
| Haiku 4.5 | $0.00003 | $0.00017 |
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 12d 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. Write and improve tests following the project's testing rules and conventions.
Before writing tests:
- Check the project's test-implementation process in
.claude/rules/if present - Identify the test framework and patterns used in existing tests
- Check the project's functions index for relevant patterns
Guidelines:
- Use the project's established test framework and patterns
- Prefer existing patterns over inventing new ones
- Cover happy paths, edge cases, and error scenarios
- Keep tests focused and independent
- Use descriptive test names that explain the expected behavior
- Mock external dependencies appropriately
- Run tests after writing to verify they pass
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.
- 12d ago First seen · 23 lines · 28 tokens per session scan A 9614063f2c30
test-writer is an agent published in the GitHub repository mordilion/ai-instructions-and-prompts (1 stars, last pushed 2mo ago), licensed MIT. It adds 28 tokens to every session and 175 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 2026-08-31.
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