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 skills/auravixstudio/caelo/write-testsnpx skills add AuraVixStudio/caelo --skill write-testsgit clone --depth 1 https://github.com/AuraVixStudio/caeloWhat 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 | $0.00020 | $0.00269 |
| Opus 5 | $0.00010 | $0.00134 |
| Sonnet 5 | $0.00004 | $0.00054 |
| Haiku 4.5 | $0.00002 | $0.00027 |
Grade A, and why
Write tests 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 3d 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
Write tests
Use this when code needs tests. Aim for tests that would actually catch a regression, not just raise the coverage number.
Steps
- Locate the harness. Find how tests are run and structured (test dir, framework, naming). Match it — do not introduce a new framework.
- Identify behavior. List the function/module's contracts: expected output, error cases, boundaries (empty, null, large, malformed input).
- Write tests. One assertion-focused test per behavior. Cover the happy path first, then the edge cases you listed. Name each test after the behavior it pins.
- Run them. Execute the suite. Confirm the new tests pass and that they fail if you break the code (a test that can't fail is worthless).
- Report. Summarize what is now covered and any behavior you deliberately left untested.
Notes
- Prefer real assertions over snapshot dumps. Keep each test independent.
- Test behavior, not implementation details — so refactors don't break the tests.
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.
- 3d ago First seen · 28 lines · 20 tokens per session scan A 6253ca2a09ca
Write tests is a skill published in the GitHub repository AuraVixStudio/caelo (22 stars, last pushed 21d ago), licensed Apache-2.0. It adds 20 tokens to every session and 269 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 2026-08-30.
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