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tdd

Test-driven development with red-green-refactor loop. Use when user wants to build features or fix bugs using TDD, mentions "red-green-refactor", wants integration tests, or asks for test-first development.

64

Quality

80%

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tessl review fix ./.cursor/skills/tdd/SKILL.md

The canonical home for this skill is tdd in mattpocock/skills

SKILL.md
Quality
Evals
Security

Quality

Content

73%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is a well-crafted, opinionated TDD process guide: concise prescriptive rules, a clearly sequenced workflow with built-in red-green validation loops, and useful checklists. Its one serious defect is that all five inline file references are dangling — the referenced files are absent from the bundle, which breaks progressive disclosure and removes the concrete examples the body defers to them.

Suggestions

Add the referenced files (tests.md, mocking.md, deep-modules.md, interface-design.md, refactoring.md) to the bundle — ideally in a references/ directory — or remove/inline the links so no reference is dangling.

Tighten the Philosophy section to its core directives (e.g., 'Tests verify behavior through public interfaces; they must survive refactors') and move the good-test/bad-test explanations into tests.md, where the body already points for examples.

Include one small concrete red-green example inline (a failing test and the minimal code that turns it green), since tests.md is currently missing and the guidance otherwise never shows what a cycle looks like in practice.

DimensionReasoningScore

Conciseness

The body is largely efficient — tight directives ("One test at a time", "Never refactor while RED. Get to GREEN first.") and a compact WRONG/RIGHT diagram — fitting the level-4 anchor 'Efficient; minor instances of over-explanation that could be trimmed'. It is not 5 because the Philosophy section spends paragraphs explaining concepts Claude already knows ("They mock internal collaborators, test private methods...") that could be reduced to the directive alone.

4 / 5

Actionability

As an instruction-only skill it gives concrete guidance — numbered workflow stages, a per-cycle checklist ("[ ] Test describes behavior, not implementation"), explicit rules, and a worked loop diagram — matching the level-4 anchor 'Mostly executable guidance... with minor gaps'. It stops short of 5 because the concrete test examples that would make it copy-paste ready are deferred to tests.md, which does not exist in the bundle.

4 / 5

Workflow Clarity

The process is clearly sequenced (Planning → Tracer Bullet → Incremental Loop → Refactor) with a built-in validation feedback loop ("RED: Write next test → fails / GREEN: Minimal code to pass → passes"), error-recovery rules ("Never refactor while RED", "Run tests after each refactor step"), and checklists for planning and each cycle. This matches the level-5 anchor 'Clear sequence with explicit validation steps; feedback loops for error recovery; checklists for complex processes', with no validation gaps to pull it to 4.

5 / 5

Progressive Disclosure

The body links five files — tests.md, mocking.md, deep-modules.md, interface-design.md, refactoring.md — but none exist anywhere in the bundle (no references/, scripts/, or assets/ directories), so every reference is dangling and navigation is broken. This fits the level-2 anchor ('references are buried'/unusable structure); it is not 3 because 'references present but not clearly signaled' understates the problem — the references are clearly signaled yet point at nothing, which is worse than imperfect signaling of files that exist.

2 / 5

Total

15

/

20

Passed

Description

78%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong description that clearly and explicitly states both what the skill does and when to use it, with natural, distinctive trigger terms. The only weakness is that the 'what' is thin — it names the red-green-refactor loop but not the skill's richer capabilities (test design principles, tracer-bullet workflow, refactoring guidance).

DimensionReasoningScore

Specificity

The description names the domain ("Test-driven development") and one concrete mechanism ("red-green-refactor loop"), matching the anchor 'Names domain and 1-2 concrete actions, but not comprehensive'. It does not list the skill's actual capabilities (test design philosophy, tracer-bullet workflow, refactoring guidance), so it falls short of the level-4 anchor 'Lists several specific actions'.

3 / 5

Completeness

It explicitly answers both questions: what ("Test-driven development with red-green-refactor loop") and when ("Use when user wants to build features or fix bugs using TDD, mentions 'red-green-refactor', wants integration tests, or asks for test-first development") with multiple concrete trigger phrases, matching the level-5 anchor. The 'when' clause is explicit and specific, so the level-4 anchor ('when' could be more explicit) does not apply.

5 / 5

Trigger Term Quality

Triggers include natural phrases users would actually say — "build features or fix bugs using TDD", "mentions 'red-green-refactor'", "wants integration tests", "asks for test-first development" — matching the level-4 anchor 'Good keyword coverage; a few natural terms missing'. It misses common variations such as "write the tests first" or "unit tests", so it does not reach the comprehensive level-5 anchor.

4 / 5

Distinctiveness Conflict Risk

Distinct triggers like "red-green-refactor" and "test-first development" carve a clear niche, fitting the level-4 anchor 'Mostly distinct; minor overlap risk with closely related skills'. It stays at 4 rather than 5 because "wants integration tests" could overlap with a general testing skill, and it is well above level 3 since the TDD framing is unmistakable.

4 / 5

Total

16

/

20

Passed

Validation

93%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

relative_links

Relative link issues: 5 missing

Warning

Total

15

/

16

Passed

Repository

SnowingFox/ai-skills

Path

.cursor/skills/tdd/SKILL.md

Reviewed

Table of Contents

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