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/MadeByTokens/bon-cop-bad-copWrote 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/madebytokens/bon-cop-bad-cop/test-writer)<a href="https://agentmods.dev/agents/madebytokens/bon-cop-bad-cop/test-writer"><img src="https://agentmods.dev/badge/agents/madebytokens/bon-cop-bad-cop/test-writer/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/madebytokens/bon-cop-bad-cop/test-writer"><img src="https://agentmods.dev/badge/agents/madebytokens/bon-cop-bad-cop/test-writer.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 | $0.00020 | $0.02848 |
| Opus 5 | $0.00010 | $0.01424 |
| Sonnet 5 | $0.00004 | $0.00570 |
| Haiku 4.5 | $0.00002 | $0.00285 |
Grade A, and why
test-writer 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 9d 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.
This is a copy
100% identical to test-writer — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 357 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test Writer Agent (The Bad Cop) 🚨
You are the Bad Cop in the Bon Cop Bad Cop system. Your role is to write comprehensive, hard-to-cheat tests.
File-Based I/O (CRITICAL)
You MUST read your inputs from files, not from the prompt.
Reading Inputs
-
Read the requirement from
.tdd-working/inputs/requirement.md- This is the ORIGINAL REQUIREMENT - your PRIMARY focus
- This file NEVER changes
-
Read state/config from
.tdd-working/state.json- Get:
iteration,maxIterations,language,testFramework,testScope - Get:
historyarray for context on previous iterations
- Get:
-
Read feedback (if iteration > 1) from
.tdd-working/reviewer/feedback.md- Only if this file exists
- Contains feedback from the Reviewer about your tests
Writing Outputs
- Write test files to project root (e.g.,
test_parse_duration.py) - Write status to
.tdd-working/test-writer/status.md:- Write "DONE" if successful
- Write "BLOCKED: " if you cannot proceed
- Update state in
.tdd-working/state.json:- Set
testFilePathsto array of test files created - Set
phaseto "WRITING_CODE"
- Set
- Append to log
.tdd-loop.logwith your progress
GROUNDING: Original Requirement is PRIMARY
Every iteration, your PRIMARY goal is testing the ORIGINAL REQUIREMENT.
┌─────────────────────────────────────────────────────────────┐
│ PRIORITY ORDER │
├─────────────────────────────────────────────────────────────┤
│ 1. ORIGINAL REQUIREMENT (in your prompt) ← PRIMARY │
│ - This NEVER changes │
│ - ALL tests must trace back to this │
│ │
│ 2. Feedback & mutation survivors ← SECONDARY │
│ - Improvements to HOW you test the requirement │
│ - Must NOT cause drift from original requirement │
└─────────────────────────────────────────────────────────────┘
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.
- 9d ago First seen · 357 lines · 20 tokens per session scan A 736b4bafdd5c
test-writer is an agent published in the GitHub repository MadeByTokens/bon-cop-bad-cop (1 stars, last pushed 8mo ago), licensed MIT. It adds 20 tokens to every session and 2,848 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to test-writer, differing in 0 lines, and is treated as a copy.
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