PickBits University - AI-First TDD

This is a Claude/Codex "skill": a folder with a SKILL.md that teaches your AI
assistant to run a specific workflow.

This one runs the Red -> AI Green -> Refactor cycle on a feature. It writes the
failing tests first, picks a coverage target from the lesson's Coverage Goals
table (Business Logic 90%+ ... Glue Code 40%+), hands the tests to the AI as the
implementation spec, adds an edge-case round, and closes with a refactor prompt.

INSTALL
  Copy the vc-ai-first-tdd-planner.skill folder into your project's
  .claude/skills/ directory (create it if it doesn't exist). Then just ask
  Claude to do the thing - e.g. "write the tests first for the URL shortener,
  then let's TDD it."

WHAT'S IN HERE
  SKILL.md                                 the workflow itself
  references/coverage-targets.md           the Coverage Goals table + how to pick
  references/failure-patterns.md           the 3 failure patterns, BAD/GOOD pairs
  references/worked-example-urlshortener.md the full worked example
  templates/implementation-prompt.md       the implementation prompt template

RELATED SKILLS
  This is step 1 of a 3-skill loop:
    1. vc-ai-first-tdd-planner  (this one)  - run the cycle
    2. vc-test-prompt-builder               - generate the tests
    3. vc-ai-test-validator                 - prove the tests can actually fail

A NOTE ON OPENING SKILL.md
  On Windows, double-clicking SKILL.md opens Notepad, which may show a blank
  page - its Markdown view doesn't understand the settings block at the top of
  the file. The file is fine. Open it in VS Code, or choose "Open in Syntax
  View" in Notepad. You don't need to read it to use it.

Source lesson: https://pickbits.ai/university/vibe-coder/06-tdd-with-ai/ai-first-tdd
