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api-testing-observability-api-mock

You are an API mocking expert specializing in realistic mock services for development, testing, and demos. Design mocks that simulate real API behavior and enable parallel development.

28

Quality

21%

Does it follow best practices?

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SecuritybySnyk

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tessl review fix ./plugins/antigravity-awesome-skills/skills/api-testing-observability-api-mock/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

20%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 is largely a template shell with abstract, high-level instructions and no concrete, executable guidance. It spends significant tokens on boilerplate sections (use/don't use, context, safety) that add little value while lacking the actionable code examples, specific tool recommendations, and validation workflows that would make it useful. The reference to an implementation playbook is a good structural choice but cannot compensate for the empty main content.

Suggestions

Add concrete, executable code examples showing how to set up a mock server (e.g., using msw, WireMock, or Express) with at least one complete working example.

Remove or drastically shorten the 'Use this skill when', 'Do not use this skill when', 'Context', and 'Safety' sections — these explain things Claude already knows and waste tokens.

Add validation checkpoints to the workflow, such as verifying the mock matches the API contract schema before serving, and testing error scenarios.

Provide the referenced 'resources/implementation-playbook.md' bundle file with actual templates, checklists, and code samples to back up the progressive disclosure reference.

DimensionReasoningScore

Conciseness

The content is verbose and padded with sections that explain things Claude already knows (what API mocking is, when to use it, generic safety advice). The 'Context' section restates the description. 'Use this skill when' and 'Do not use this skill when' sections add little actionable value. Nearly every token could be tightened or removed.

1 / 3

Actionability

There are no concrete code examples, commands, or executable guidance anywhere. The instructions are abstract directives like 'Clarify the API contract' and 'Define mock routes' without showing how. No specific tools, frameworks, or copy-paste-ready snippets are provided.

1 / 3

Workflow Clarity

The instructions section provides a rough sequence of steps (clarify contract → define routes → provide fixtures → document running), but there are no validation checkpoints, no feedback loops, and no explicit verification steps. The sequence is present but lacks rigor.

2 / 3

Progressive Disclosure

There is a reference to 'resources/implementation-playbook.md' for detailed content, which is a good signal of progressive disclosure. However, no bundle files were provided, so the reference is unverifiable. The main file itself contains mostly filler rather than a useful overview, and the single reference is not well-signaled with descriptions of what's inside.

2 / 3

Total

6

/

12

Passed

Description

22%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 description reads more like a persona prompt ('You are an API mocking expert') than a skill description, using first/second person framing rather than third person. It lacks concrete actions, explicit trigger conditions, and natural user keywords, making it difficult for Claude to reliably select this skill from a pool of alternatives.

Suggestions

Replace the persona-style framing with third-person action statements listing specific capabilities, e.g., 'Creates mock API endpoints, generates realistic response fixtures, simulates error codes and latency, and produces OpenAPI-compatible stubs.'

Add an explicit 'Use when...' clause with natural trigger terms, e.g., 'Use when the user asks about mocking APIs, creating stubs, fake endpoints, test doubles, mock servers, or needs to simulate API responses for testing or parallel development.'

Remove the second-person 'You are' framing entirely, as skill descriptions should describe what the skill does in third person, not address Claude directly.

DimensionReasoningScore

Specificity

The description uses vague language like 'design mocks that simulate real API behavior' and 'enable parallel development' without listing concrete actions. No specific operations (e.g., generate mock endpoints, create response fixtures, simulate error codes) are mentioned.

1 / 3

Completeness

The description vaguely addresses 'what' (design mocks) but lacks any explicit 'when' clause or trigger guidance. There is no 'Use when...' statement, which per the rubric should cap completeness at 2, and the 'what' is too vague to even reach that level.

1 / 3

Trigger Term Quality

Includes some relevant keywords like 'API mocking', 'mock services', 'development', 'testing', and 'demos', but misses common user terms like 'stub', 'fake API', 'mock server', 'test doubles', 'API simulation', or specific tool names.

2 / 3

Distinctiveness Conflict Risk

The 'API mocking' domain is somewhat specific and distinguishable from general coding or testing skills, but the broad mention of 'development, testing, and demos' could overlap with general testing or API development skills.

2 / 3

Total

6

/

12

Passed

Validation

90%

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

Validation — 10 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

10

/

11

Passed

Repository
popey/claude-code-skills
Reviewed

Table of Contents

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