Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add sequenzia/agent-alchemy/plugin install agent-alchemy-tdd-toolsWrote 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/sequenzia/agent-alchemy/tdd-cycle)<a href="https://agentmods.dev/skills/sequenzia/agent-alchemy/tdd-cycle"><img src="https://agentmods.dev/badge/skills/sequenzia/agent-alchemy/tdd-cycle.svg" alt="Measured on agentmods" 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 | $0.00051 | $0.05815 |
| Opus 5 | $0.00026 | $0.02908 |
| Sonnet 5 | $0.00010 | $0.01163 |
| Haiku 4.5 | $0.00005 | $0.00581 |
Grade A, and why
tdd-cycle 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 4d 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 — 728 lines — stays where its author put it; the contents beside it link to each section on GitHub.
TDD Cycle Skill
Run a full RED-GREEN-REFACTOR Test-Driven Development workflow for a feature. This skill drives the entire TDD lifecycle: understand the feature, write failing tests, confirm they fail (RED), implement minimal code to make them pass (GREEN), then refactor while keeping tests green (REFACTOR).
CRITICAL: Complete ALL 7 phases. The workflow is not complete until Phase 7: Report is finished. After completing each phase, immediately proceed to the next phase without waiting for user prompts.
Core Principles
- Tests before implementation -- Write tests first. The tests define what the code should do. Implementation follows from tests, not the other way around.
- Minimal implementation -- Write only the code needed to make failing tests pass. No extra features, no premature optimization, no speculative abstractions.
- Regression protection -- Existing tests must continue passing at every phase. Zero tolerance for regressions.
- Phase gate enforcement -- Each phase must complete and verify before the next begins. RED verification is mandatory. GREEN verification is mandatory.
- Behavior over implementation -- Tests verify what code does (inputs, outputs, side effects), not how it does it internally.
- Autonomous after plan confirmation -- The user confirms the plan once in Phase 3. After that, the entire RED-GREEN-REFACTOR cycle runs without interruption.
AskUserQuestion is MANDATORY
IMPORTANT: You MUST use the AskUserQuestion tool for ALL questions to the user. Never ask questions through regular text output.
- Plan confirmation -> AskUserQuestion
- Framework selection -> AskUserQuestion
- Clarifying questions -> AskUserQuestion
- Error recovery options -> AskUserQuestion
Text output should only be used for presenting information, summaries, and progress updates.
NEVER do this (asking via text output):
Should I proceed with this plan?
1. Yes
2. No, modify it
ALWAYS do this (using AskUserQuestion tool):
AskUserQuestion:
questions:
- header: "TDD Plan Confirmation"
question: "Review the TDD plan above. Ready to proceed?"
options:
- label: "Proceed"
description: "Run the full RED-GREEN-REFACTOR cycle autonomously"
- label: "Modify plan"
description: "Adjust tests, scope, or approach before starting"
- label: "Cancel"
description: "Cancel the TDD workflow"
multiSelect: false
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.
- 4d ago First seen · 728 lines · 51 tokens per session scan A ec6e927b9cc9
tdd-cycle is a skill published in the GitHub repository sequenzia/agent-alchemy (44 stars, last pushed 3mo ago), licensed MIT. It adds 51 tokens to every session and 5,815 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 2026-09-03.
Other skills, from other repositories
auto-loop
TDD-based autonomous development loop with checkpoint recovery and observability changelog.
workflow
Run the complete 5-step development workflow: focus problem → prevent over-development → test-first (TDD) → document → smart commit. Use when starting a new feature, or when the user runs /workflow or asks for the full development flow.
test-first
Drive one feature through a strict TDD Red-Green-Refactor cycle with checklists for each phase. Use when implementing new functionality test-first, or when the user runs /test-first.
linked-intent-dev
Guide for linked-intent development (LID). Consult for ALL code changes. Walks changes through a mode-aware six-phase workflow (HLD → LLD → EARS → intent-narrowing edge audit → tests-first → code) with mandatory stops between each phase. Bugs walk the arrow like any other change — no short-circuit. Enforces cascade…
plan
Analyzes architecture, selects patterns, assesses testability, then decomposes work into ordered TDD tasks with exact verification commands and explicit acceptance mapping. Works from an approved spec (zuvo:brainstorm output) or directly from a user-provided description.
improving-tests
Improve test design, speed, and coverage with behavior-focused tests, useful seams, characterization tests, TDD, and test refactoring. Use when improving tests, optimizing slow suites, adding coverage, refactoring brittle tests, removing test waste, or working test-first. NOT for fixing production bugs (use…