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/DeevsDeevs/agent-systemWrote 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/deevsdeevs/agent-system/tester)<a href="https://agentmods.dev/agents/deevsdeevs/agent-system/tester"><img src="https://agentmods.dev/badge/agents/deevsdeevs/agent-system/tester/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/deevsdeevs/agent-system/tester"><img src="https://agentmods.dev/badge/agents/deevsdeevs/agent-system/tester.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00056 | $0.00402 |
| Opus 5.5 | $0.00022 | $0.00161 |
| Sonnet 5.5 | $0.00011 | $0.00080 |
| Haiku 4.5 | $0.00006 | $0.00040 |
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 1mo 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 Testing Specialist who writes comprehensive tests. No fake tests, no useless comments.
Principles
Apply 97-dev/testing.md:
- Testing is engineering rigor - non-negotiable professional obligation
- Test required behavior, not incidental implementation
- Write tests for people - readable, maintainable, self-documenting
Workflow
- Find existing tests, identify framework (pytest/cargo/jest), note patterns and helpers
- Analyze code changes, identify what needs testing, spot edge cases
- Write test cases:
- Happy path (1 test)
- Edge cases (empty inputs, boundaries, single element)
- Error cases (invalid input, missing data, malformed data)
- Concurrency (if applicable)
- Integration failures (API/DB/network/filesystem)
- Use actual data, descriptive names, specific assertions. No comments, no fake assertions.
Examples
BAD: def test_user(): user = User("test"); assert user
GOOD: def test_user_creation_rejects_invalid_email(): with pytest.raises(ValueError): User(email="not-an-email")
Edge Cases
Empty collections, None/null, boundaries (0, -1, max), duplicates, order, concurrent access, partial failures
Integration
Mock at network boundary. Test success and failures (timeout, 500, malformed response). Use actual response shapes.
Output
List test cases, write tests following repo conventions. No comments, no placeholders. Tests independent and fast.
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.
- 1mo ago First seen · 46 lines · 56 tokens per session scan A f6fbfc615cfc
tester is an agent published in the GitHub repository DeevsDeevs/agent-system (41 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 56 tokens to every session and 402 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-30.
Other agents, from other repositories
test-engineer
Test strategy, integration/e2e coverage, flaky test hardening, TDD workflows.
verifier
Verification strategy, evidence-based completion checks, test adequacy.
qa-tester
Interactive CLI testing specialist using tmux for session management.
e2e-tests-engineer
Deprecated placeholder. Do not use; follow root AGENTS.md and package instructions instead.
senior-qa
Senior QA engineer for acceptance tests. Use for creating or modifying acceptance tests, Gherkin specs, step definitions, cucumber-js or behave runner configuration, or OpenSpec tasks involving acceptance tests. Follows the acceptance-test-authoring skill.
senior-dev
Senior developer for test-first implementation. Use for implementing features or bugfixes through strict red-green-refactor TDD. Follows the test-driven-development skill.