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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?

Impact

No eval scenarios have been run

SecuritybySnyk

Passed

No known issues

Optimize this skill with Tessl

npx tessl skill review --optimize ./skills/antigravity-api-testing-observability-api-mock/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

20%

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 meta-template with boilerplate sections rather than actionable, concrete guidance for API mocking. It lacks any executable code examples, specific tool recommendations, or concrete mock definitions. The content tells Claude what to do at a high level but doesn't provide the specific knowledge or patterns that would make Claude more effective at the task.

Suggestions

Add concrete, executable code examples showing how to set up a mock server (e.g., using MSW, WireMock, or Express with sample route definitions and fixture data).

Replace vague instructions like 'Clarify the API contract' with specific templates or schemas showing what a mock definition looks like (e.g., a sample OpenAPI spec mapped to mock responses).

Remove boilerplate sections that don't add value ('Use this skill when', 'Do not use this skill when', 'Context', 'Limitations') or condense them to 1-2 lines maximum.

Provide the referenced `resources/implementation-playbook.md` bundle file, or inline the most critical patterns and examples directly in the skill body.

DimensionReasoningScore

Conciseness

The content is verbose and explains concepts Claude already knows. Sections like 'Use this skill when', 'Do not use this skill when', 'Context', and 'Limitations' are padded with obvious guidance that doesn't add actionable value. The 'Safety' section states obvious best practices. Much of this is meta-instruction rather than substantive content.

1 / 3

Actionability

The skill provides no concrete code, commands, or executable examples. Instructions like 'Clarify the API contract' and 'Define mock routes' are vague directives without specific implementation guidance. There are no code snippets, no example mock definitions, no sample server configurations—everything is abstract description.

1 / 3

Workflow Clarity

The Instructions section provides a rough sequence of steps (clarify contract → define routes → provide fixtures → document), but there are no validation checkpoints, no feedback loops, and no concrete verification steps. The sequence is present but lacks the specificity needed for reliable execution.

2 / 3

Progressive Disclosure

The skill references `resources/implementation-playbook.md` for detailed implementation, which is a good progressive disclosure pattern. However, no bundle files are provided, so the reference is unverifiable. The main file itself contains too much boilerplate that could be trimmed rather than properly structured content that warrants splitting.

2 / 3

Total

6

/

12

Passed

Description

22%

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

The description is too vague and reads more like a persona definition ('You are an API mocking expert') than a skill description. It lacks concrete actions, explicit trigger guidance, and uses second/implied person framing rather than third person. The absence of a 'Use when...' clause and specific capabilities makes it difficult for Claude to reliably select this skill from a pool of alternatives.

Suggestions

Add a 'Use when...' clause with explicit triggers, e.g., 'Use when the user asks to mock an API, create stub endpoints, generate fake API responses, or set up a mock server for testing.'

List specific concrete actions the skill performs, e.g., 'Generates mock API endpoints, creates realistic response fixtures with proper status codes, simulates error scenarios, and produces OpenAPI-compatible mock configurations.'

Rewrite in third person voice (e.g., 'Designs and generates mock API services...') instead of the current persona-style 'You are an expert' framing.

DimensionReasoningScore

Specificity

The description uses vague language like 'design mocks that simulate real API behavior' and 'enable parallel development' without listing concrete actions. It doesn't specify what actions are performed (e.g., generate mock endpoints, create response fixtures, simulate error codes).

1 / 3

Completeness

The description addresses 'what' only vaguely (design mocks) and completely lacks a 'Use when...' clause or any explicit trigger guidance for when Claude should select this skill. Per the rubric, a missing 'Use when...' clause caps completeness at 2, and the weak 'what' brings it to 1.

1 / 3

Trigger Term Quality

It includes some relevant terms like 'API mocking', 'mock services', 'development', 'testing', and 'demos', which users might naturally say. However, it misses common variations like 'stub', 'fake API', 'mock server', 'test doubles', or specific tools/formats.

2 / 3

Distinctiveness Conflict Risk

The term 'API mocking' provides some distinctiveness, but the broad mentions of 'development', 'testing', and 'demos' could overlap with many other development-related skills. It's somewhat specific to mocking but not sharply delineated.

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.

Validation10 / 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
boisenoise/skills-collections
Reviewed

Table of Contents

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