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 rules/cembasaranoglu/crafting-system-claude/20-testing-validationgit clone --depth 1 https://github.com/cembasaranoglu/crafting-system-claudeWrote 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/rules/cembasaranoglu/crafting-system-claude/20-testing-validation)<a href="https://agentmods.dev/rules/cembasaranoglu/crafting-system-claude/20-testing-validation"><img src="https://agentmods.dev/badge/rules/cembasaranoglu/crafting-system-claude/20-testing-validation.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 | $0.00004 | $0.00141 |
| Opus 5 | $0.00002 | $0.00071 |
| Sonnet 5 | $0.00001 | $0.00028 |
| Haiku 4.5 | $0.00000 | $0.00014 |
Grade A, and why
20-testing-validation 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
Testing and Validation
- Prefer many deterministic unit tests, fewer integration tests, minimal e2e tests.
- Add negative-path, boundary, regression, and error tests, not only happy paths.
- Avoid hidden network/cloud/daemon dependencies in unit tests.
- Avoid sleeps; use fake clocks, synchronization, or polling with deadlines.
- Use contract tests for public APIs, CLIs, SDKs, configs, events, file formats, and generated artifacts.
- Do not weaken tests, linting, type checks, or security checks to make a change pass.
- Do not claim validation ran unless it actually ran in this session.
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 · 15 lines · 4 tokens per session scan A a7514abce9fc
20-testing-validation is a cursor rule published in the GitHub repository cembasaranoglu/crafting-system-claude (5 stars, last pushed 4mo ago), licensed MIT. It adds 4 tokens to every session and 141 once invoked, about $0.0000 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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