test-driven-development SKILL.md skillA
test-driven-development from flieber-inc/devcake is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add flieber-inc/devcake/test-driven-development@git:20260720.fa58fb9Pins git:20260720.fa58fb9 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- flieber-inc/devcake
- Path
app/devcake/skills/test-driven-development/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260720.fa58fb9, committed Jul 20, 2026
- First version recorded
- Jul 17, 2026
- Size
- 3,454 bytes
- Repository stars
- 29
- License
- GPL-3.0
Strict red-green-refactor discipline at public seams — write a failing test, watch it fail, write minimal code to pass. Use when implementing features, bug fixes with a known reproduction, or new modules, before production code. Prefer port/fakes over private-helper tests. Companion: verification-before-completion for proof after green; systematic-debugging when the failure’s cause is unclear.
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
# Test-driven development Write the test first. Watch it fail. Write the minimum code to pass. **Iron law:** no production behavior without a failing test that names it first. If you did not watch the test fail, you do not know it tests the right thing. ## When this skill applies **Always for:** new features, bug fixes with a reproduction, behavior changes, new public modules or ports. **Usually skip (document why):** pure renames, docs-only, config/copy, mechanical follow-the-existing-pattern refactors with no behavior change — still run the existing suite. Do not use this skill to redefine mission playbooks or legal outcomes. It owns **how** you construct tested code, not **what step** you are on. ## Public seams only - Tests hit the **public interface** under test: functions, port Protocols, HTTP paths the product owns — not private helpers or call-count spies on internal collaborators. - Prefer fakes at **port** seams. Fakes must honor the Protocol contract (Liskov): same error classes and observable behavior shape as production. - Assertions use known literals and domain rules — do not recompute the same algorithm as production to derive the expected value. …
Read the whole file at its exact version.
How to install
mdr add flieber-inc/devcake/test-driven-development@sha256:b92bf198f578c9ecThe line at the top of this page pins the label git:20260720.fa58fb9, 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_5vwgbn653nwsztfk)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Jul 17, 2026 and Jul 20, 2026, about one every 2 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260720.fa58fb9 latest | 2026-07-20 | fa58fb9 | 3,454 B | A | view · diff |
| git:20260717.70feb23 | 2026-07-17 | 70feb23 | 9,959 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 (3454 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
flieber-inc/devcake · 29 stars · license GPL-3.0 · pushed 2026-10-25 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_5vwgbn653nwsztfk GET https://markdownregistry.com/api/v1/resolve?ref=flieber-inc/devcake/test-driven-development GET https://markdownregistry.com/api/v1/blob/b92bf198f578c9ec985d30b2be20f4fb630e9192d3c4e7f22c16b247a13fc338
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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