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/humzakt/dev-starter-kit/testinggit clone --depth 1 https://github.com/humzakt/dev-starter-kitWhat 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 | $0.00000 | $0.00270 |
| Opus 5 | $0.00000 | $0.00135 |
| Sonnet 5 | $0.00000 | $0.00054 |
| Haiku 4.5 | $0.00000 | $0.00027 |
Grade A, and why
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 Rules
Structure
- File:
tests/test_<module_name>.py - Class:
Test<ModuleName> - Method:
test_<function_name>[_<scenario>]
Patterns
- Use pytest fixtures for setup/teardown
- Mock external dependencies — no real network calls, no real database queries
- Use
unittest.mock.patchorpytest-mockfor mocking - Use
tmp_pathfixture for temporary files
What to Test
- Happy path (expected inputs → expected outputs)
- Edge cases (empty inputs, None, boundary values, large inputs)
- Error cases (invalid inputs → appropriate exceptions)
- Integration points (verify correct calls to external dependencies)
What NOT to Test
- Private methods directly (test through public API)
- Third-party library internals
- Exact log messages (test behavior, not messages)
Running Tests
# All tests
pytest tests/ -v
# Single file
pytest tests/test_module.py -v
# Single test
pytest tests/test_module.py::TestModule::test_function -v
# With coverage
pytest tests/ -v --cov=src --cov-report=term-missing
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 · 44 lines · 0 tokens per session scan A c9b88bd98986
testing is a cursor rule published in the GitHub repository humzakt/dev-starter-kit (3 stars, last pushed 6mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 270 tokens. 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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