use-tdd

use-tdd is a skill for Claude Code from blockmatic/basilic. It costs 24 tokens per session (236 once invoked), scanned A, original, MIT.

A guide for test-driven development, or TDD: writing tests before the code they check.

In plain words
What is it for?
Use it when you explicitly want to build a feature through a TDD workflow.
Why use it?
It gives feature work a step-by-step testing process, helping define expected behaviour before implementation.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter. Also seen: installed under .agents/ (shared by several agents).

Good fit Use it when you explicitly want to build a feature through a TDD workflow.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/blockmatic/basilic/use-tdd
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 blockmatic/basilic --skill use-tdd
Clone the repo
git clone --depth 1 https://github.com/blockmatic/basilic

Made for: Claude Code.

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 use-tdd

README.md
[![agentmods](https://agentmods.dev/badge/skills/blockmatic/basilic/use-tdd.svg)](https://agentmods.dev/skills/blockmatic/basilic/use-tdd)
Your own site
<a href="https://agentmods.dev/skills/blockmatic/basilic/use-tdd"><img src="https://agentmods.dev/badge/skills/blockmatic/basilic/use-tdd.svg" alt="Measured on agentmods" height="20"></a>
Per session 24 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 236 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 $0.00024 $0.00236
Opus 5 $0.00012 $0.00118
Sonnet 5 $0.00005 $0.00047
Haiku 4.5 $0.00002 $0.00024

Measured 2d ago against content hash a0607faf4fc3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

use-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 2d 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.

.agents/skills/workflow/use-tdd/SKILL.md · 27 lines

What it actually says

Purpose and inputs

Use TDD only when the user asked for it or the repository requires it. Follow the repo testing MDX and vitest-v4 (or the stack's test skill). Do not commit unless asked.

Steps

  1. Red: Write a failing test for the desired behavior. Use real APIs where the repo tests do; mock only at documented boundaries.
  2. Green: Write the smallest implementation that passes that test.
  3. Refactor: Improve structure while tests stay green. Follow lint and file-organization rules.
  4. Repeat for the next increment. Run the focused test file each cycle, then the affected suite.

Verification

  • The new test failed before the implementation existed (or that fact is explained).
  • The focused tests pass after green and after refactor.
  • No unsolicited commit.

Handoff

Report the test files, the increment, and remaining uncovered behavior.

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. 2d ago Changed · +13 lines · -2 tokens per session a0607faf4fc3
  2. 5d ago First seen · 14 lines · 26 tokens per session scan A de99b4982fa8

Subscribe to this mod's changes

use-tdd is a skill published in the GitHub repository blockmatic/basilic (89 stars, last pushed 2d ago), licensed MIT. It adds 24 tokens to every session and 236 once invoked, about $0.0001 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.