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/arango-solutions/arango-sparql-pyWrote 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/arango-solutions/arango-sparql-py/test-what-you-touch)<a href="https://agentmods.dev/rules/arango-solutions/arango-sparql-py/test-what-you-touch"><img src="https://agentmods.dev/badge/rules/arango-solutions/arango-sparql-py/test-what-you-touch.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 5.1 | $0.00395 | $0.00395 |
| Opus 5 | $0.00198 | $0.00198 |
| Sonnet 5 | $0.00079 | $0.00079 |
| Haiku 4.5 | $0.00040 | $0.00040 |
Grade A, and why
test-what-you-touch 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 7d 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 What You Touch
"Every code change deserves a test change."
If you changed code, you changed behavior. If you changed behavior, tests must verify it.
The Testing Mandate
| Code Change Type | Required Test Change |
|---|---|
| New function | New unit test |
| New endpoint | New integration test |
| Bug fix | Regression test (would have caught the bug) |
| Refactor | Run existing tests, add any missing coverage |
| New error path | Test that exercises the error path |
| Config change | Test with different config values |
Test Coverage
For new functions, test: happy path, error paths (invalid/empty input), edge cases (boundary values).
For bug fixes: write a regression test that reproduces the original bug, then verify the fix.
For refactors: all existing tests MUST still pass. If they don't cover the refactored path, add tests FIRST.
The "Touched Files" Rule
For every file you modify:
- Is there a corresponding test file? If no → create one
- Does the test file cover the code you changed? If no → add coverage
- Did you run the tests after your change? If no → run them now
Test Quality
- Deterministic — no flaky tests
- Fast — slow tests don't get run
- Isolated — no shared state between tests
- Clear names —
TestX_WhenY_ShouldZformat - Assert behavior — not just "no panic"
Anti-Patterns
- "I tested manually" → Write an automated test
- "I'll add tests later" → Tests are written NOW
- "It's just a small change" → Small changes still need tests
If you wrote it, test it.
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.
- 7d ago First seen · 53 lines · 395 tokens per session scan A 2910d6428608
test-what-you-touch is a cursor rule published in the GitHub repository arango-solutions/arango-sparql-py (2 stars, last pushed yesterday), licensed MIT. It adds 395 tokens to every session, about $0.0020 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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