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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.

62

Quality

72%

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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

62%Scale 1-3

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

This is a well-structured TDD workflow skill with clear sequencing and good anti-pattern guidance. Its main weaknesses are the lack of concrete, executable code examples (no actual test/implementation shown) and some verbosity in the philosophy and anti-pattern sections that explain concepts Claude already knows. The references to supporting files are well-placed but unverifiable without bundle files.

Suggestions

Add a concrete, executable code example showing one full RED→GREEN→REFACTOR cycle (e.g., a simple function with a real test in a specific language/framework) to boost actionability.

Trim the philosophy section significantly—Claude understands testing principles. Focus on the project-specific conventions and the vertical-slice mandate, which are the genuinely novel instructions.

Provide the referenced bundle files (tests.md, mocking.md, etc.) or remove references to non-existent files to avoid confusion.

DimensionReasoningScore

Conciseness

The philosophy section over-explains what good vs bad tests are—concepts Claude already understands well. The anti-pattern section is valuable but somewhat verbose in its explanation. The workflow and checklist sections are reasonably tight.

2 / 3

Actionability

The workflow provides clear steps and checklists, but lacks concrete, executable code examples. The RED→GREEN diagrams are illustrative but abstract—no actual test code or implementation code is shown. A TDD skill would benefit greatly from a concrete example showing a real test→implementation cycle.

2 / 3

Workflow Clarity

The workflow is clearly sequenced (Planning → Tracer Bullet → Incremental Loop → Refactor) with explicit validation checkpoints (checklists per cycle, 'never refactor while RED', run tests after each refactor step). The vertical slice approach is well-articulated with a clear feedback loop.

3 / 3

Progressive Disclosure

References to supporting files (tests.md, mocking.md, deep-modules.md, interface-design.md, refactoring.md) are present and one-level deep, which is good. However, no bundle files were provided, so these references are unverifiable. The main file itself includes substantial philosophical content that could be split out, and the inline content is somewhat long for an overview.

2 / 3

Total

9

/

12

Passed

Description

82%Scale 1-3

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

This is a solid description with a clear 'Use when...' clause and good trigger term coverage. Its main weakness is that the capability description is somewhat abstract—it names the methodology rather than listing the concrete steps Claude will perform. The broad terms like 'build features' and 'fix bugs' also introduce some conflict risk with other development-oriented skills.

Suggestions

Add specific concrete actions like 'Writes failing tests first, implements minimal code to pass, then refactors for clean design' to improve specificity.

Narrow the broad triggers 'build features' and 'fix bugs' by qualifying them, e.g., 'build features using a test-first approach' to reduce overlap with general development skills.

DimensionReasoningScore

Specificity

Names the domain (TDD) and mentions the red-green-refactor loop, but doesn't list specific concrete actions like 'write failing tests', 'implement minimal code to pass', 'refactor for clean design'. The actions are implied by the methodology name rather than explicitly enumerated.

2 / 3

Completeness

Clearly answers both 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 explicit trigger guidance.

3 / 3

Trigger Term Quality

Includes strong natural trigger terms: 'TDD', 'red-green-refactor', 'integration tests', 'test-first development', 'build features', 'fix bugs'. These cover a good range of terms users would naturally say when wanting this workflow.

3 / 3

Distinctiveness Conflict Risk

While 'red-green-refactor' and 'TDD' are distinctive, terms like 'build features', 'fix bugs', and 'integration tests' are quite broad and could overlap with general coding or testing skills. The description could conflict with a general testing skill or a feature development skill.

2 / 3

Total

10

/

12

Passed

Validation

100%

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

Validation11 / 11 Passed

Validation for skill structure

No warnings or errors.

Repository
SnowingFox/ai-skills
Reviewed

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