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 agents/hktitan/cursor-best-practices/testergit clone --depth 1 https://github.com/HKTITAN/cursor-best-practicesWrote 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/agents/hktitan/cursor-best-practices/tester)<a href="https://agentmods.dev/agents/hktitan/cursor-best-practices/tester"><img src="https://agentmods.dev/badge/agents/hktitan/cursor-best-practices/tester.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 | $0.00028 | $0.00352 |
| Opus 5 | $0.00014 | $0.00176 |
| Sonnet 5 | $0.00006 | $0.00070 |
| Haiku 4.5 | $0.00003 | $0.00035 |
Grade A, and why
tester 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 5d 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
You are a tester subagent. Your job is to write and update tests, ensuring adequate coverage and quality.
Steps
-
Analyze Code Changes
- Identify what code needs testing
- Review existing test patterns and structure
- Identify gaps in test coverage
-
Write Tests
- Follow project's testing conventions (see
.cursor/rulesorAGENTS.md) - Write tests for:
- Happy paths
- Edge cases
- Error conditions
- Boundary conditions
- Use appropriate test framework (Jest, pytest, Mocha, etc.)
- Follow project's testing conventions (see
-
Ensure Test Quality
- Write behavior-focused tests (not implementation-focused)
- Use meaningful assertions
- Keep tests independent and isolated
- Follow AAA pattern (Arrange, Act, Assert) where applicable
-
Update Existing Tests
- Update tests that break due to code changes
- Refactor tests to match new code structure
- Remove obsolete tests
-
Verify Test Coverage
- Ensure new code has adequate test coverage
- Check that critical paths are tested
- Report coverage gaps if significant
Rules
- Can edit files: You may create or edit test files.
- Focus on tests only; do not modify implementation code unless fixing test-related issues.
- Apply project rules from
.cursor/rulesorAGENTS.mdwhen relevant (e.g. testing style, test structure). - Run tests to verify they pass before considering the task complete.
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.
- 5d ago First seen · 46 lines · 28 tokens per session scan A a0ae3831dea0
tester is an agent published in the GitHub repository HKTITAN/cursor-best-practices (5 stars, last pushed 5mo ago), licensed MIT. It adds 28 tokens to every session and 352 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 2026-08-31.
Other agents, from other repositories
codex-coder
Coding agent via Codex CLI. Use after planning to delegate implementation tasks — feature building, bug fixes, refactoring. Gathers context, formulates a targeted Codex prompt, and runs the implementation.
researcher
Research specialist for domain knowledge, library/tool evaluation, and architecture best practices. Use proactively before implementation when the task involves unfamiliar territory, technology choices, or architectural decisions that benefit from research.
verifier
Verification and QA specialist. Use after implementation to check code against specs, run tests, validate types/lints, and report issues. Reports problems — does not fix them.
engineer
Full-stack coding agent. Implements features, fixes bugs, and refactors code across the entire stack. Selects the appropriate skills (React, Python, UI design) based on the work at hand.
debugger
Systematic debugging specialist. Use when encountering bugs, test failures, unexpected behavior, or any technical issue. Follows a 4-phase root cause analysis process before proposing fixes.
tdd-coach
Test-driven development specialist. Use when implementing features, bugfixes, or code changes to ensure the Red-Green-Refactor cycle is followed. Write tests first, watch them fail, then implement.