tdd-engine

tdd-engine is a skill for Claude Code, Codex from lync-cyber/CataForge. It costs 53 tokens per session (5,917 once invoked), scanned A, original, MIT.

A TDD workflow engine that coordinates separate agents for the RED, GREEN, and REFACTOR stages. RED writes a failing test, GREEN implements the behaviour, and REFACTOR improves the code while keeping the tests passing.

In plain words
What is it for?
Use it to run unit-test-driven tasks in standard, lightweight, or prototype modes, dispatch implementation agents, optionally refactor code, and update task progress.
Why use it?
It separates each development stage into focused work and helps coordinate independent tasks within a sprint.

Skill for Claude CodeCodex

Install

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.

agentmods
npx agentmods add skills/lync-cyber/cataforge/tdd-engine
Any agent
npx skills add lync-cyber/CataForge --skill tdd-engine
Clone the repo
git clone --depth 1 https://github.com/lync-cyber/CataForge

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for tdd-engine

README.md
[![agentmods](https://agentmods.dev/badge/skills/lync-cyber/cataforge/tdd-engine.svg)](https://agentmods.dev/skills/lync-cyber/cataforge/tdd-engine)
Your own site
<a href="https://agentmods.dev/skills/lync-cyber/cataforge/tdd-engine"><img src="https://agentmods.dev/badge/skills/lync-cyber/cataforge/tdd-engine.svg" alt="Measured on agentmods" height="20"></a>
Per session 53 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,917 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00053 $0.05917
Opus 5 $0.00026 $0.02959
Sonnet 5 $0.00011 $0.01183
Haiku 4.5 $0.00005 $0.00592

Measured 5d ago against content hash 297757f2cb5f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

tdd-engine 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.

.cataforge/skills/tdd-engine/SKILL.md · 371 lines

How it starts

The opening of the file, as written. The whole thing — 371 lines — stays where its author put it; the contents beside it link to each section on GitHub.

TDD引擎 (tdd-engine)

能力边界

  • 能做: 指导orchestrator编排TDD三阶段子代理(RED/GREEN/REFACTOR)、light-dispatch/light-inline/standard 档位路由、prototype 主线程内联实现、同 sprint_group 独立任务并行调度、定义子代理prompt模板
  • 不做: 需求分析、架构设计、文档生成、集成测试 / E2E 测试(由 testing skill 负责,本 skill 限单元测试粒度的 RED/GREEN/REFACTOR)

架构说明

orchestrator作为主线程Agent,在Phase 5逐任务执行时调用本skill。每个TDD阶段作为独立子代理启动,拥有独立上下文窗口,避免阶段间上下文污染。

orchestrator (主线程)
  ├─ 通过调度接口启动 → RED SubAgent (test-writer) — 独立上下文
  ├─ 收集RED产出 → 通过调度接口启动 → GREEN SubAgent (implementer) — 独立上下文
  ├─ implementer self-report `refactor_needed=true` 或 `tdd_refactor: required` → REFACTOR SubAgent (refactorer)
  └─ 汇总产出 → 更新dev-plan任务状态

四档执行模式(触发条件唯一定义在 §执行流程 任务路由分支):

执行位置
standard RED + GREEN + REFACTOR(条件) 三次 dispatch
light-dispatch implementer 一次 dispatch(合并 RED+GREEN)
light-inline orchestrator 主线程内联 implementer 行为,零子代理 boot
prototype-inline 同 light-inline,强制跳过 REFACTOR

Mid-Progress Drop Contract

避免子代理在末尾 finalize 集中产出导致 task-notification truncation(征兆:100+ tools / 100K+ tokens / 5min+ 被打断;<agent-result> 不返回但 artifact 已部分落地)。触发(任一命中):loc_estimate > MID_PROGRESS_LOC(缺字段取 len(AC) × 30)或 len(tdd_acceptance) > 6。命中时 implementer dispatch prompt 强制注入:

Mid-progress 落盘

  1. Write 全部目标文件的空骨架(import + export stub + describe(...) / 函数签名占位),按依赖序落盘——被导入文件先于引用它的文件(写盘纪律见 SUB-AGENT-PROTOCOLS §并行/多文件写盘纪律)
  2. 逐 AC 迭代填充实现 + 测试
  3. 每完成一条 AC 立刻运行 {test_command_fast}(按需附 file 过滤)验证
  4. 禁止末尾一次 Edit 堆所有 AC 实现 + 全套断言

适用:standard Step 3 GREEN ✅;light-dispatch ✅;light-inline / prototype-inline ❌(主线程产出,token 由主线程窗口管理,不需此契约)。契约失效(仍 truncation)→ ORCHESTRATOR-RECOVERY-PROTOCOLS §Sub-Agent Truncation Recovery Protocol 主线程接管。

TDD 子代理共享约束

以下约束适用于所有 TDD 子代理,通过 AGENT.md 的 disallowedTools 和本节定义:

  • 各 Step 的 dispatch 块:角色定义 / 返回格式 / 异常处理由对应 AGENT.md 经 subagent_type 自动加载,prompt 仅内联任务上下文,各 Step 不再重述
  • AskUserQuestion 不可用。如需用户输入,返回 blocked 并在 <questions> 描述问题,orchestrator 以 continuation 重启
  • 返回 <agent-result> 格式(详见 dispatch-prompt.md §COMMON-SECTIONS)
  • blocked 时可追加 <questions> 字段

Read the full file on GitHub · 371 lines

Files

What ships with it

6 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.

Changes

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.

  1. 5d ago First seen · 371 lines · 53 tokens per session scan A 297757f2cb5f

Subscribe to this mod's changes

tdd-engine is a skill published in the GitHub repository lync-cyber/CataForge (128 stars, last pushed 1mo ago), licensed MIT. It adds 53 tokens to every session and 5,917 once invoked, about $0.0003 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 2026-08-30.