implement-with-tdd SKILL.md skillA
implement-with-tdd from stevepolitodesign/skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add stevepolitodesign/skills/implement-with-tdd@git:20260916.114dbbfPins git:20260916.114dbbf in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- stevepolitodesign/skills
- Path
implement-with-tdd/SKILL.md- Versions recorded
- 5
- Latest version
- git:20260916.114dbbf, committed Sep 16, 2026
- First version recorded
- Aug 20, 2026
- Size
- 7,160 bytes
- Repository stars
- 10
- License
- none declared
Implement a SPEC, plan, or feature outside-in, with TDD.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Implement with TDD Work from the outside in and let each failure name the next move. Stop at shameless green; a later step refactors. The discipline exists because you're fluent enough to write plausible code for almost anything, and plausible isn't correct. A failing test tells them apart. ## What you were handed The thing to build: `$ARGUMENTS` If that's empty, ask. If it's a path, read it. Take the acceptance criteria as the scope. Those are behavior, and behavior is what you can test. A suggested design, a test path, an ordering: that's a guess from a session that never ran the suite. Yours will run it, so your evidence is better. Where the repo contradicts the plan the repo is right — say so rather than diverge quietly. A `## Where to look` section is the exception to that distrust, not to the scope rule. Those paths are where a prior session already found the relevant code, so they save you the search and not the judgment: open them before you go looking for anything else, and treat nothing on the list as work you owe. The criteria are still the whole scope. If a path is gone or turns out to be irrelevant, skip it and say so in the report — don't edit the SPEC. …
Read the whole file at its exact version.
How to install
mdr add stevepolitodesign/skills/implement-with-tdd@sha256:9661eb4b400642b1The line at the top of this page pins the label git:20260916.114dbbf, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_xziutxunmg3u2dhm)
7 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 5 versions of this file, between Aug 20, 2026 and Sep 16, 2026, about one every 7 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260916.114dbbf latest | 2026-09-16 | 114dbbf | 7,160 B | A | view · diff |
| git:20260915.6a51426 | 2026-09-15 | 6a51426 | 6,682 B | A | view · diff |
| git:20260903.d25ad65 | 2026-09-03 | d25ad65 | 6,713 B | A | view · diff |
| git:20260824.84f78a9 | 2026-08-24 | 84f78a9 | 6,923 B | A | view · diff |
| git:20260820.9f0498a | 2026-08-20 | 9f0498a | 6,285 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (7160 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
stevepolitodesign/skills · 10 stars · license none declared · pushed 2026-11-05 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_xziutxunmg3u2dhm GET https://markdownregistry.com/api/v1/resolve?ref=stevepolitodesign/skills/implement-with-tdd GET https://markdownregistry.com/api/v1/blob/9661eb4b400642b19e7f874044ea3bbd79ef4f120f9d69ce9b5617f32685d235
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
More from stevepolitodesign/skills
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