tdd-workflow

tdd-workflow is a skill for Claude Code from MadAppGang/magus. It costs 51 tokens per session (2,031 once invoked), scanned A, original, MIT.

A guide for using test-driven development (TDD), where you write a failing test, make it pass, and then improve the code. It keeps this Red-Green-Refactor cycle organised while a test watcher runs.

In plain words
What is it for?
It helps develop and refine code with Jest, Vitest, Cargo Watch, or pytest-watch while reading results from a separate terminal pane.
Why use it?
It prevents the agent from losing track of whether a test is failing, passing, or still running. This makes repeated test-and-code iterations more predictable.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter.

Part of the terminal plugin — 5 skills, 7 commands, 1 agent shipped together

Good fit It helps develop and refine code with Jest, Vitest, Cargo Watch, or pytest-watch while reading results from a separate terminal pane.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/madappgang/magus/tdd-workflow
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.

Any agent
npx skills add MadAppGang/magus --skill tdd-workflow
Clone the repo
git clone --depth 1 https://github.com/MadAppGang/magus

Made for: Claude Code.

Or install terminal, the plugin that ships this one along with the rest of its 5 skills, 7 commands, 1 agent.

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-workflow

README.md
[![agentmods](https://agentmods.dev/badge/skills/madappgang/magus/tdd-workflow.svg)](https://agentmods.dev/skills/madappgang/magus/tdd-workflow)
Your own site
<a href="https://agentmods.dev/skills/madappgang/magus/tdd-workflow"><img src="https://agentmods.dev/badge/skills/madappgang/magus/tdd-workflow.svg" alt="Measured on agentmods" height="20"></a>
Per session 51 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,031 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 5.1 $0.00051 $0.02031
Opus 5 $0.00026 $0.01015
Sonnet 5 $0.00010 $0.00406
Haiku 4.5 $0.00005 $0.00203

Measured today against content hash 8fa9819c5a0d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

tdd-workflow 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 today.

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.

plugins/terminal/skills/tdd-workflow/SKILL.md · 201 lines

How it starts

The opening of the file, as written. The whole thing — 201 lines — stays where its author put it; the contents beside it link to each section on GitHub.

TDD Workflow — Red-Green-Refactor Protocol

This skill teaches the protocol Claude follows AFTER a test watcher is running. For watcher setup (starting the watcher pane and managing long-running processes), see terminal:terminal-interaction. For framework-specific pass/fail/running/idle signals, see terminal:framework-signals.

The TDD loop requires a dedicated pane topology: Claude edits code in one pane while a persistent test watcher runs in a second pane. Claude reads the watcher with watch-pane and capture-pane but never restarts it.

Overview

Pane Topology

┌──────────────────────┬────────────────────┐
│  Claude work pane    │  Test Watcher      │
│  (Bash / code edit)  │  (helper pane)     │
└──────────────────────┴────────────────────┘

The left (work) pane is where Claude runs file edits and any auxiliary commands. The right (watcher) pane runs the test framework in watch mode for the entire session. Claude only reads the watcher pane — it never sends keystrokes to it except at teardown.

State Machine

The TDD protocol is a 5-state machine. Always know which state you are in before taking an action.

RED    → parse failure (file:line:test name from watch-pane output)
         → edit code → save → enter WAITING

WAITING → watch-pane fires "pattern:RUNS|Running" → change detected
         → if watch-pane times out: re-save with touch, watch-pane again
         → proceed to poll for RED or GREEN

GREEN  → report pass count → leave watcher running → ask user to continue

COMPILE_ERROR → fix compile error first → re-enter WAITING

IDLE   → Ctrl+C watcher pane → report summary: N tests fixed

State Transitions

From Condition To
RED File saved, watch-pane detects change WAITING
WAITING watch-pane fires pass pattern GREEN
WAITING watch-pane fires fail pattern RED
WAITING watch-pane fires compiler error pattern COMPILE_ERROR
COMPILE_ERROR Compile error resolved, file saved WAITING
GREEN User asks to continue / next failing test RED
GREEN User asks to stop IDLE
Any User explicitly stops IDLE

Read the full file on GitHub · 201 lines

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. today Changed 8fa9819c5a0d
  2. 4d ago First seen · 201 lines · 51 tokens per session scan A 2f9e483452e2

Subscribe to this mod's changes

tdd-workflow is a skill published in the GitHub repository MadAppGang/magus (9 stars, last pushed today), licensed MIT. It adds 51 tokens to every session and 2,031 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 2026-09-04.