atdd skillA
atdd is agent-read markdown (skill) from swingerman/engineer: 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"..
Indexed from public GitHub and served as immutable, content-addressed versions. Install it pinned to an exact SHA-256 with the mdr CLI, and every file is verified against the hash recorded here before it reaches your agent. The deterministic audit below grades the latest version, and the same file always earns 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@git:20260525.78c79demdr add swingerman/engineer/atdd@sha256:1f704df598a9f478Pin to a label to follow the author's releases, or to a sha256 to freeze the exact bytes forever. Either way the resolved hash is written to mdr.lock, and mdr install reproduces it on any machine.
[](https://markdownregistry.com/a/art_7atzgeqah2q526yw)
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Versions
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260525.78c79de latest | 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 (11168 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 · 150 stars · license MIT · pushed 2026-09-22 · 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/1f704df598a9f4783e14bae8bd3b0ac396a3a9a4d4da714de0bb0202745e8dfb
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