atdd SKILL.md skillA
atdd from swingerman/engineer is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add swingerman/engineer/atdd@git:20261020.a98004ePins git:20261020.a98004e in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- swingerman/engineer
- Path
skills/atdd/SKILL.md- Versions recorded
- 6
- Latest version
- git:20261020.a98004e, committed Oct 20, 2026
- First version recorded
- May 18, 2026
- Size
- 11,438 bytes
- Repository stars
- 162
- License
- MIT
Use to drive feature work through the Acceptance Test Driven Development workflow — Given/When/Then specs before code, a project-specific test pipeline, and two parallel test streams (acceptance + unit). Triggers — "/atdd", "build a feature", "implement a feature", "add functionality", "start development", "write acceptance tests", "write specs", "use ATDD", "use TDD with acceptance tests".
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
# Acceptance Test Driven Development
Enforce the ATDD workflow for feature development. This methodology is
adapted from Robert C. Martin's acceptance test approach.
## Core Principle
> "The two different streams of tests cause Claude to think much more
> deeply about the structure of the code."
> — Robert C. Martin
Two test streams constrain development:
- **Acceptance tests** define WHAT the system does (external observables)
- **Unit tests** define HOW the system does it (internal structure)
Both must pass. Neither alone is sufficient.
## Workflow
Follow these steps strictly, in order. Do not skip steps.
Before Step 1, create one TodoWrite todo per step of this workflow (Steps 1–7),
all at once — the full list up front, as a roadmap. Flip each todo to
`in_progress` / `completed` as you go. See
`${CLAUDE_PLUGIN_ROOT}/references/progress-indicator.md`.
### Step 1: Understand the Feature
Before writing anything, understand what is being built:
- Ask clarifying questions about the feature's purpose
- Identify the domain language (what terms do users/stakeholders use?)
- Determine success criteria: what observable behavior proves it works?
…Read the whole file at its exact version.
How to install
mdr add swingerman/engineer/atdd@sha256:b096b3dd3a54c50aThe line at the top of this page pins the label git:20261020.a98004e, 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_7atzgeqah2q526yw)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 6 versions of this file, between May 18, 2026 and Oct 20, 2026, about one every 31 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261020.a98004e latest | 2026-10-20 | a98004e | 11,438 B | A | view · diff |
| git:20260525.78c79de | 2026-05-25 | 78c79de | 11,168 B | A | view · diff |
| git:20260525.947d66d | 2026-05-25 | 947d66d | 11,243 B | A | view · diff |
| v0.6.0 | 2026-05-19 | 6a6a913 | 11,258 B | A | view · diff |
| v0.6.0 | 2026-05-18 | 3055aeb | 11,002 B | A | view · diff |
| v0.6.0 | 2026-05-18 | 8f9f593 | 10,642 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 (11438 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
swingerman/engineer · 162 stars · license MIT · pushed 2026-10-27 · branch master
API
GET https://markdownregistry.com/api/v1/artifacts/art_7atzgeqah2q526yw GET https://markdownregistry.com/api/v1/resolve?ref=swingerman/engineer/atdd GET https://markdownregistry.com/api/v1/blob/b096b3dd3a54c50a429ad642c846936fa0f7eb38afc73284bd6ac0a1dd393866
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.
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