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 georgekhananaev/claude-skills-vault --skill plan-to-tddgit clone --depth 1 https://github.com/georgekhananaev/claude-skills-vaultWrote 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/georgekhananaev/claude-skills-vault/plan-to-tdd)<a href="https://agentmods.dev/skills/georgekhananaev/claude-skills-vault/plan-to-tdd"><img src="https://agentmods.dev/badge/skills/georgekhananaev/claude-skills-vault/plan-to-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/georgekhananaev/claude-skills-vault/plan-to-tdd"><img src="https://agentmods.dev/badge/skills/georgekhananaev/claude-skills-vault/plan-to-tdd.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00049 | $0.01667 |
| Opus 5 | $0.00024 | $0.00834 |
| Sonnet 5 | $0.00010 | $0.00333 |
| Haiku 4.5 | $0.00005 | $0.00167 |
Grade A, and why
plan-to-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 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.
How it starts
The opening of the file, as written. The whole thing — 277 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Plan-to-TDD
Transform feature plans → test-driven implementation using Outside-In methodology.
When to Use
Invoke when:
- Converting plan docs from
docs/plan/YYYY/MM/to code - Designing test structure for new features
- Applying TDD w/ architectural awareness
- Bridging system design to implementation
Prerequisites
- Reference:
.claude/skills/test-levelsfor Unit/Integration/E2E guidance - Plan files in
docs/plan/YYYY/MM/YYYY_MM_DD_HHmm__FEATURE_NAME.md
Related Skills
| Skill | Location | Phase |
|---|---|---|
doc-navigator |
.claude/skills/doc-navigator |
Load/Design - find existing patterns |
uiux-toolkit |
.claude/skills/uiux-toolkit |
Verify - 9-domain UX evaluation |
test-levels |
.claude/skills/test-levels |
Plan/Execute - test distribution |
Outside-In Workflow
SYSTEM DESIGN → INTEGRATION TESTS (Red) → TDD UNITS → E2E VALIDATION
Phase Flow
┌─────────────────────────────────────────────────┐
│ 1. SYSTEM DESIGN │
│ Components → Contracts → Dependencies │
└────────────────────┬────────────────────────────┘
▼
┌─────────────────────────────────────────────────┐
│ 2. INTEGRATION TESTS (Red) │
│ Validate component contracts - tests FAIL │
└────────────────────┬────────────────────────────┘
▼
┌─────────────────────────────────────────────────┐
│ 3. TDD UNIT PHASE │
│ Red → Green → Refactor per unit │
└────────────────────┬────────────────────────────┘
▼
┌─────────────────────────────────────────────────┐
│ 4. E2E VALIDATION │
│ Complete user journey verification │
└─────────────────────────────────────────────────┘
Execution Steps
Step 1: Load Plan
Input: docs/plan/YYYY/MM/YYYY_MM_DD_HHmm__FEATURE_NAME.md
Extract:
- User story & acceptance criteria
- Components & dependencies
- Data flows
- Technical constraints
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.
- 9d ago First seen · 277 lines · 49 tokens per session scan A 544bc4d262ee
plan-to-tdd is a skill published in the GitHub repository georgekhananaev/claude-skills-vault (28 stars, last pushed 1mo ago), licensed MIT. It adds 49 tokens to every session and 1,667 once invoked, about $0.0002 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
test-first-bugs
Enforces a test-driven bug-fixing workflow. Use when a user reports a bug, failing code, an error, or asks to fix something.
skill-authoring
Guide creating Claude Code skills with TDD and persuasion principles. Use for new skill development.
subagent-testing
Test skills via TDD in fresh subagents. Use when validating behavior or preventing bias.
nl-to-constraints
Transforms natural language requirements (user stories, verbal descriptions, business rules) into formal specifications and constraints. Use when converting informal requirements into structured, testable specifications with explicit constraints. Outputs in multiple formats including BDD-style Given-When-Then, JSON…
lsp-refactoring
Intelligent code refactoring using IDE-level tools (rename, find-references, go-to-definition), AST-aware pattern matching, and TDD verification. Use for safe, large-scale refactoring with precision.
tdd-workflow
A test-first development workflow, commonly called TDD, where a failing test is written before the code that should make it pass. The cycle then adds the smallest working change and cleans it up.