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 skills add dinhanhthi/coding-friend --skill cf-tddgit clone --depth 1 https://github.com/dinhanhthi/coding-friendWrote 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/skills/dinhanhthi/coding-friend/cf-tdd)<a href="https://agentmods.dev/skills/dinhanhthi/coding-friend/cf-tdd"><img src="https://agentmods.dev/badge/skills/dinhanhthi/coding-friend/cf-tdd/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/skills/dinhanhthi/coding-friend/cf-tdd"><img src="https://agentmods.dev/badge/skills/dinhanhthi/coding-friend/cf-tdd.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 | $0.00140 | $0.01411 |
| Opus 5.5 | $0.00056 | $0.00564 |
| Sonnet 5.5 | $0.00028 | $0.00282 |
| Haiku 4.5 | $0.00014 | $0.00141 |
Grade A, and why
cf-tdd 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.
How it starts
The opening of the file, as written. The whole thing — 124 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Implementation Workflow
Custom Guide
bash "<plugin-root>/lib/load-custom-guide.sh" cf-tdd
If the block above printed anything, apply only the ## Before, ## Rules, and ## After sections; if it shows the raw command instead of output, re-run that exact load-custom-guide.sh fence now.
Mode Detection
Determine the implementation mode BEFORE doing anything else:
- Check if the user's invocation or task description contains
--add-tests - Check if
.coding-friend/config.jsonexists and has"tdd": true - Check if the user's invocation or task description contains
--auto(orthogonal to mode — autopilot can combine with both Direct and TDD mode).
Result:
--add-testspresent ORtdd: truein config → TDD mode. Show:> TDD mode enabled — RED → GREEN → REFACTOR. → TDD mode: Read<plugin-root>/skills/cf-tdd/modes/tdd-mode.mdnow and follow RED→GREEN→REFACTOR.- Neither → Direct mode (default). Show:
> Direct mode — implementing without new tests - Additionally, if
--autois present → Autopilot active. Show:> 🤖 Autopilot enabled — will auto-review, auto-fix Critical+Important, and auto-commit after implementation.
Skip Conditions
Check these BEFORE starting. If a skip condition is met, bypass the workflow entirely and proceed directly to implementation.
Auto-skip whitelist
If ALL changed/new files match these extensions, skip entirely — note why and proceed:
- Styles:
.css,.scss,.sass,.less,.styl - Docs:
.md,.mdx,.txt,.rst - Config:
.json,.yaml,.yml,.toml,.env,.ini,.lock,.config
--no-tdd flag
Deprecated — direct mode is now the default. If present, acknowledge and proceed in direct mode:
--no-tddis now the default. Proceeding in direct mode.
--auto flag
Note: --auto enables the Autopilot Post-Implementation Loop. It does NOT change the implementation mode itself. → When --auto is active, Read <plugin-root>/skills/cf-tdd/modes/autopilot-loop.md now and run that loop instead of the standard Review Reminder.
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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 Changed 889be763c498
- 1mo ago Changed · -50 lines · +4 tokens per session 85f65ca2bd52
- 1mo ago First seen · 174 lines · 136 tokens per session scan A 95326fcc6b97
cf-tdd is a skill published in the GitHub repository dinhanhthi/coding-friend (4 stars, last pushed 2d ago), licensed MIT. It adds 140 tokens to every session and 1,411 once invoked, about $0.0006 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 2026-08-31.
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