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test-driven-development

Use when implementing any feature or bugfix, before writing implementation code - write the test first, watch it fail, write minimal code to pass; ensures tests actually verify behavior by requiring failure first

Quality

84%

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SKILL.md
Quality
Evals
Security

Quality

Content

81%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 TDD workflow skill with an exemplary RED/GREEN/REFACTOR sequence, explicit validation checkpoints, a feedback loop for stalled progress, and concrete good/bad code examples. Its main weaknesses are minor: a placeholder identifier in the flagship example, unstated dependencies on environment-specific tooling, and a few trimmable annotation lines.

DimensionReasoningScore

Conciseness

The body is mostly lean with phase sections, tight checklists, and no concept explanations Claude already knows, but the example annotations ('this is a STRONG sign that this is testing something real') and the embedded system-reminder aside are minor over-explanation that could be trimmed. It sits between 'efficient' (4) and 'every token earns its place' (5), closer to 4.

4 / 5

Actionability

Provides executable bash commands ('npm test path/to/test.test.ts'), complete TypeScript test and implementation examples with good/bad contrasts, and concrete confirm-checklists. Minor gaps keep it below 5: the RED example calls 'foobar.retryOperation' as a placeholder, and steps depend on environment-specific tooling ('nori-task-runner', '.agency/plugins/nori/...') whose availability is unstated.

4 / 5

Workflow Clarity

A 7-step numbered sequence (RED → test-quality evaluation → verify fail → GREEN → verify pass → refactor → verify pass) with explicit validation checkpoints at steps 3, 5, and 7, per-phase confirm checklists ('Test fails (not errors)', 'Failure message is expected'), and an error-recovery feedback loop ('If you go through three loops without making progress, switch to... creating-debug-tests-and-iterating'). This matches the anchor for clear sequence with explicit validation and feedback loops.

5 / 5

Progressive Disclosure

No bundle files exist, so the skill is a single self-contained file with clear phase sections (RED, Verify RED, GREEN, Verify GREEN, REFACTOR) and one clearly signaled one-level-deep fallback reference to the nori debug skill. It exceeds 50 lines, so the simple-skill 5 exception does not apply, but structure and placement are good — matching the anchor for good structure with minor organization gaps.

4 / 5

Total

17

/

20

Passed

Description

80%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 states both the TDD procedure and an explicit 'Use when' trigger with concrete, natural phrases. Its weakness is scope: 'any feature or bugfix' makes the trigger extremely broad, raising conflict risk with general coding skills, and a few natural synonyms (TDD, test-driven, unit tests) would improve trigger coverage.

Suggestions

Narrow the trigger scope or add distinguishing qualifiers (e.g., 'Use when the user requests test-first development, TDD, or asks that tests be written before implementation') to reduce conflict with general implementation skills.

Add natural synonyms such as 'TDD', 'test-driven development', or 'unit tests' to the trigger phrasing so users who name the methodology directly still match.

Mention the refactor step ('then refactor while keeping tests green') so the stated capabilities cover the full workflow described in the body.

DimensionReasoningScore

Specificity

Lists several concrete actions — 'write the test first, watch it fail, write minimal code to pass' — plus the mechanism 'ensures tests actually verify behavior by requiring failure first'. It is not a 5 because coverage has minor gaps: the refactor and re-verify phases from the body are absent, so the action list is not comprehensive.

4 / 5

Completeness

Explicitly answers both questions: what ('write the test first, watch it fail, write minimal code to pass; ensures tests actually verify behavior') and when ('Use when implementing any feature or bugfix, before writing implementation code'). Both are concrete and explicit, matching the top anchor with concrete trigger phrases rather than the 4 anchor where the when-clause is only adequate.

5 / 5

Trigger Term Quality

Includes natural phrases users would say: 'implementing any feature or bugfix', 'before writing implementation code', 'write the test first'. A few natural terms are missing — no 'TDD', 'test-driven', or 'unit test' synonyms — so it falls short of the comprehensive-synonyms anchor at 5 but is clearly above 'some relevant keywords with missing variations' at 3.

4 / 5

Distinctiveness Conflict Risk

The what ('write the test first, watch it fail, write minimal code to pass') carves out a clear TDD niche, but the trigger 'any feature or bugfix' fires on virtually all coding work, creating real overlap with general implementation and testing skills. That is more than 'minor overlap risk' (4) but far more distinctive than the generic examples at 2, so 'somewhat specific but could still overlap' (3) is the best fit.

3 / 5

Total

16

/

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.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

microsoft/FluidFramework

Path

.agency/plugins/nori/skills/test-driven-development/SKILL.md

Reviewed

Table of Contents

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