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/panozzaj/cursor-rules/selective-testinggit clone --depth 1 https://github.com/panozzaj/cursor-rulesWhat 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 | $0.00256 | $0.00256 |
| Opus 5 | $0.00128 | $0.00128 |
| Sonnet 5 | $0.00051 | $0.00051 |
| Haiku 4.5 | $0.00026 | $0.00026 |
Grade A, and why
selective-testing 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 Strategy for Faster Feedback
When iterating on specific functionality or making localized changes:
-
Identify Relevant Tests: Based on the code modified, determine the subset of tests most likely to be impacted.
-
Run Targeted Tests: Execute only the identified subset of tests to get fast feedback on the immediate changes. Use
pytest -m <marker>orpytest -k <keyword>orpytest <path/to/test_file.py>. Document which command you are running and why. -
Iterate: Use the results of the targeted tests to refine the changes.
After completing a logical unit of work, fixing a bug, or before considering a feature stable:
- Run Full Suite: Execute the entire test suite (e.g., by running
pytestwith no specific targets) to ensure the changes haven't introduced regressions elsewhere in the codebase. - Verify: Ensure all tests pass before proceeding to the next major step or concluding the task.
The goal is to balance speed during development with the confidence provided by a full test suite run.
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 · 22 lines · 256 tokens per session scan A f509f4794561
selective-testing is a cursor rule published in the GitHub repository panozzaj/cursor-rules (3 stars, last pushed 1y ago), licensed MIT. It adds 256 tokens to every session, about $0.0013 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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