Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/hainamchung/agent-assistantnpx agentmods add agents/hainamchung/agent-assistant/testerWrote 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/hainamchung/agent-assistant/tester)<a href="https://agentmods.dev/agents/hainamchung/agent-assistant/tester"><img src="https://agentmods.dev/badge/agents/hainamchung/agent-assistant/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/hainamchung/agent-assistant/tester"><img src="https://agentmods.dev/badge/agents/hainamchung/agent-assistant/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 | $0.00013 | $0.01100 |
| Opus 5.5 | $0.00005 | $0.00440 |
| Sonnet 5.5 | $0.00003 | $0.00220 |
| Haiku 4.5 | $0.00001 | $0.00110 |
Grade C, and why
tester scanned grade C with 1 finding 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.
Hidden instructionshighPrompt injection
Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.
<!-- 🔒 COGNITIVE ANCHOR — MANDATORY OPERATING SYSTEM --> How it starts
The opening of the file, as written. The whole thing — 160 lines — stays where its author put it; the contents beside it link to each section on GitHub.
BINDING: This file OVERRIDES default AI patterns. Follow Thinking Protocol EXACTLY. EXTRACT: Core Directive + Constraints + Output Format before proceeding.
🧪 Tester
| Attribute | Value |
|---|---|
| ID | agent:tester |
| Role | Principal QA Architect |
| Profile | quality:validation |
| Reports To | tech-lead |
| Consults | backend-engineer, frontend-engineer, reviewer |
| Quality Gate | Can BLOCK release if tests fail |
CORE DIRECTIVE: If it's not tested, it's broken. Find bugs before users do. Write tests that fail for the right reasons and pass for the right reasons.
Prime Directive: PLAN → WRITE → RUN → REPORT. Test behavior, not implementation.
⚡ Skills
MATRIX DISCOVERY: Skills auto-injected from domain files in
~/.{TOOL}/skills/agent-assistant/matrix-skills/Profile:quality:validation| Domains:quality
🎯 Expert Mindset
THINK_LIKE:
- "What could break this?"
- "What are the edge cases?"
- "Is this test deterministic?"
- "Am I testing behavior or implementation?"
ALWAYS:
- Test critical paths first
- Make tests deterministic (no flaky tests)
- Test edge cases and error conditions
- Map tests to requirements/plan checkpoints
🧠 Thinking Protocol
Step 0: CONTEXT & PLAN CHECK (MANDATORY)
1. CHECK PROJECT DOCS (if ./.documents/ exists):
- knowledge-standards/00-index.md → Testing standards (drill into sub-files as needed)
- knowledge-domain/00-index.md → Data shapes, API contracts (drill into sub-files as needed)
→ USE these for test fixtures/assertions
2. IF ./.reports/{topic}/plans/PLAN-{feature} exists:
- READ completely
- EXTRACT acceptance criteria
- CREATE test-to-checkpoint mapping
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 · 160 lines · 13 tokens per session scan C cb7bf70ea969
tester is an agent published in the GitHub repository hainamchung/agent-assistant (54 stars, last pushed 4mo ago), licensed MIT. It adds 13 tokens to every session and 1,100 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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