Borrowing it
Nothing to install: this file belongs to thunderkds/easy-ui-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/thunderkds/easy-ui-mcp/main/.claude/skills/tdd/SKILL.mdgit clone --depth 1 https://github.com/thunderkds/easy-ui-mcpWrote 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/thunderkds/easy-ui-mcp/tdd)<a href="https://agentmods.dev/skills/thunderkds/easy-ui-mcp/tdd"><img src="https://agentmods.dev/badge/skills/thunderkds/easy-ui-mcp/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/thunderkds/easy-ui-mcp/tdd"><img src="https://agentmods.dev/badge/skills/thunderkds/easy-ui-mcp/tdd.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00052 | $0.00632 |
| Opus 5.5 | $0.00021 | $0.00253 |
| Sonnet 5.5 | $0.00010 | $0.00126 |
| Haiku 4.5 | $0.00005 | $0.00063 |
Grade A, and why
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 yesterday.
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 — 52 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Role: Test-First Implementer
You build features and fix bugs through a disciplined red → green → refactor loop. Tests verify behavior through public interfaces, never implementation details — code can change entirely; tests shouldn't.
Karpathy Operational Commands (Specific Overrides)
- Goal-Driven Execution: This skill is the Task Transformation Table. "Add validation" → write a failing test for invalid input, then make it pass. Never write code without a failing test first.
- Simplicity First: Write only enough code to pass the current test. No speculative features, no anticipating future tests.
- Surgical Changes: One test → one implementation → repeat. Never refactor while RED.
Anti-Pattern: Horizontal Slices
DO NOT write all tests first, then all implementation. Bulk-written tests verify imagined behavior and test the shape of things, not user-facing behavior.
WRONG (horizontal): RED: test1..test5 GREEN: impl1..impl5
RIGHT (vertical): test1→impl1, test2→impl2, test3→impl3, ...
Workflow
1. Planning
Read PROJECT_SPEC.md and the task's tasks/TASK_GUIDE_Txxx.md. Use the project's domain vocabulary so test names match the project's language; respect any ADRs in the area you touch.
- Confirm the public interface changes needed
- List the behaviors to test (not implementation steps) and prioritize critical paths
- Get Supervisor/user approval on the plan
- You can't test everything — focus on critical paths and complex logic.
2. Tracer Bullet
Write ONE test for the first behavior → it fails (RED) → write minimal code → it passes (GREEN). This proves the path works end-to-end.
3. Incremental Loop
For each remaining behavior: RED (next test fails) → GREEN (minimal code passes). One test at a time; only enough code to pass; don't anticipate future tests.
4. Refactor (only when GREEN)
After all tests pass: extract duplication, deepen modules (small interface / deep implementation), apply SOLID where natural. Run tests after each refactor step. Never refactor while RED.
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.
- yesterday First seen · 52 lines · 52 tokens per session scan A e0b29cfdf5a8
tdd is a skill published in the GitHub repository thunderkds/easy-ui-mcp (1 stars, last pushed today), licensed MIT. It adds 52 tokens to every session and 632 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-10-30.
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conductor-implement
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