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test-driven-development

Guides TDD (test-driven development) with red-green-refactor workflows, test-first feature delivery, bug reproduction through failing tests, behavior-focused assertions, and refactoring safety. Use when writing unit tests, implementing new functions, adding test coverage, fixing regressions, changing APIs, or restructuring code under test — especially when a user says "write tests first", "TDD", or "test before code".

74

Quality

91%

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SKILL.md
Quality
Evals
Security

Quality

Content

86%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.

A well-structured, highly actionable skill body: executable examples in two languages, concrete commands, behavior-focused anti-patterns with WHY explanations, and a clean reference table pointing to a real, well-organized bundle. The minor gaps are boundary-section redundancy that could be trimmed and the absence of an error-recovery feedback loop in the workflow.

Suggestions

Consolidate 'When to Use', 'When Not to Use', and 'Scope' into a single compact section — they currently restate the same boundary information three times, and the frontmatter description already carries the triggers.

Add an explicit error-recovery branch to the workflow, e.g., 'If the failing test fails for the wrong reason, fix the test before implementing' — this closes the feedback loop needed for the top workflow-clarity anchor.

Consider replacing or augmenting the trivial add(2, 3) example with one that shows a behavior-first API decision, since the current example spends lines demonstrating something Claude already knows how to write.

DimensionReasoningScore

Conciseness

The body is efficient with no tutorial-style explanation of concepts Claude already knows — every example is concrete code — but the 'When to Use', 'When Not to Use', and 'Scope In/Out' sections (~25 lines) largely restate boundary information already in the description, and the trivial add() example is trimmable. This matches the 'minor instances of over-explanation that could be trimmed' anchor rather than the 'noticeably verbose' or 'every token earns its place' anchors.

4 / 5

Actionability

Fully executable TypeScript and Elixir examples covering the RED-GREEN-REFACTOR cycle, copy-paste-ready commands (bun test --watch, mix test), and BAD/GOOD code contrasts in every anti-pattern match the top anchor: 'copy-paste ready code or commands; specific examples cover the common cases'.

5 / 5

Workflow Clarity

The 5-step workflow has a clear sequence and an explicit validation checkpoint ('Run tests and verify failure is for the expected reason') plus a green-suite guard on refactoring, matching the 'clear sequence with most checkpoints present' anchor. It falls short of the top anchor because there is no error-recovery feedback loop (e.g., what to do when RED fails for the wrong reason).

4 / 5

Progressive Disclosure

Verified against the actual bundle: the body is a genuine navigation hub, six references are surfaced in a clearly-labeled topic table, all referenced paths resolve to real one-level-deep files in references/, and the remaining 37 bundle files stay out of context. This matches the 'clear overview with well-signaled one-level-deep references; easy navigation' anchor.

5 / 5

Total

18

/

20

Passed

Description

96%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: concrete third-person capability list, an explicit and well-phrased 'Use when...' clause with natural quoted trigger phrases, and a well-defined TDD niche. The only weakness is that a few broad triggers ('changing APIs', 'restructuring code under test') could overlap with general refactoring or testing skills.

DimensionReasoningScore

Specificity

Lists five concrete capabilities ('red-green-refactor workflows', 'test-first feature delivery', 'bug reproduction through failing tests', 'behavior-focused assertions', 'refactoring safety') in third-person voice, matching the comprehensive-coverage anchor; no meaningful gaps place it below the anchor for 'several specific actions with minor gaps'.

5 / 5

Completeness

Explicitly answers both 'what' (the five capabilities) and 'when' ('Use when writing unit tests, implementing new functions... especially when a user says...') with concrete trigger phrases, exactly matching the top anchor; the 'when' clause is fully explicit, so the 4 anchor's 'could be more explicit' does not apply.

5 / 5

Trigger Term Quality

Includes natural user phrases in quotes ('write tests first', 'TDD', 'test before code') plus synonyms like 'unit tests', 'test coverage', and 'regressions', matching the comprehensive-synonym anchor rather than the 'a few natural terms missing' anchor.

5 / 5

Distinctiveness Conflict Risk

TDD is a clear niche with distinct quoted triggers, but broad triggers like 'changing APIs, or restructuring code under test' create minor overlap risk with general refactoring and testing skills, matching the 'mostly distinct; minor overlap risk' anchor rather than the minimal-conflict anchor.

4 / 5

Total

19

/

20

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.

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
pantheon-org/tekhne
Reviewed

Table of Contents

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