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tdd

Test-driven development. Use when the user wants to build features or fix bugs test-first, mentions "red-green-refactor", or wants integration tests.

62

Quality

72%

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tessl review fix ./.agents/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 skill provides a well-structured TDD workflow with clear sequencing and good anti-pattern guidance. Its main weaknesses are the lack of concrete, executable code examples showing an actual TDD cycle in practice, and some verbosity in the philosophy section explaining testing 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 cycle (e.g., a Python/JS test that fails, then the minimal implementation that makes it pass) to replace or supplement the abstract test1→impl1 placeholders.

Trim the philosophy section — Claude already understands integration vs unit testing and implementation coupling. Reduce to 2-3 bullet points of project-specific conventions rather than general testing philosophy.

Provide the referenced bundle files (tests.md, mocking.md, refactoring.md) or remove the references if they don't exist, as broken references reduce trust in the skill.

DimensionReasoningScore

Conciseness

The philosophy section spends significant tokens explaining what good vs bad tests are — concepts Claude already understands well. The anti-pattern section, while valuable, is somewhat verbose in its explanation. The ASCII diagrams and checklists are efficient, but overall the skill could be tightened by ~30%.

2 / 3

Actionability

The workflow steps are clear but lack concrete, executable code examples. The test/implementation examples use abstract placeholders (test1→impl1) rather than real code showing an actual TDD cycle. There are no language-specific executable examples demonstrating how to write a failing test and then make it pass.

2 / 3

Workflow Clarity

The workflow is clearly sequenced (Planning → Tracer Bullet → Incremental Loop → Refactor) with explicit validation checkpoints (checklists per cycle, 'run tests after each refactor step', 'never refactor while RED'). The feedback loop of RED→GREEN is well-defined with clear rules about when to proceed.

3 / 3

Progressive Disclosure

References to tests.md, mocking.md, refactoring.md, CONTEXT.md, and /codebase-design skill are present and one-level deep, which is good. However, no bundle files were provided, so these references are unverifiable. The philosophy section is fairly long and could potentially be split out, keeping SKILL.md as a leaner 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 terms specific to TDD methodology. Its main weakness is that the capability description is somewhat high-level—it says 'test-driven development' but doesn't enumerate the specific actions the skill performs (e.g., writing test stubs, running test suites, refactoring steps). There's also moderate overlap risk with general testing or coding skills.

Suggestions

Add more specific concrete actions like 'Writes failing tests first, implements minimal code to pass, then refactors. Generates test stubs, runs test suites, and iterates through red-green-refactor cycles.'

Differentiate from general testing skills by clarifying what this skill does NOT cover (e.g., 'Not for writing tests after implementation or for unit test generation without TDD workflow').

DimensionReasoningScore

Specificity

Names the domain (test-driven development) and mentions some actions ('build features', 'fix bugs test-first'), but doesn't list specific concrete actions like 'write failing tests, implement minimal code to pass, refactor code'. The capabilities are described at a high level rather than with multiple specific actions.

2 / 3

Completeness

Clearly answers both 'what' (test-driven development for building features or fixing bugs) and 'when' (explicit 'Use when...' clause covering test-first approach, red-green-refactor mentions, and integration test requests).

3 / 3

Trigger Term Quality

Includes strong natural trigger terms: 'test-driven development', 'test-first', 'red-green-refactor', 'integration tests', 'build features', 'fix bugs'. These are terms users would naturally say when wanting TDD guidance.

3 / 3

Distinctiveness Conflict Risk

While 'red-green-refactor' and 'test-first' are distinctive TDD triggers, terms like 'build features', 'fix bugs', and 'integration tests' could overlap with general coding skills or testing skills that aren't specifically TDD-focused.

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
coder/agent-tty
Reviewed

Table of Contents

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