generating-test-doubles
This skill uses the test-doubles-generator plugin to automatically create mocks, stubs, spies, and fakes for unit testing. It analyzes dependencies in the code and generates appropriate test doubles based on the chosen testing framework, such as Jest, Sinon, or others. Use this skill when you need to generate test doubles, mocks, stubs, spies, or fakes to isolate units of code during testing. Trigger this skill by requesting test double generation or using the `/gen-doubles` or `/gd` command.
Install with Tessl CLI
npx tessl i github:jeremylongshore/claude-code-plugins-plus-skills --skill generating-test-doubles82
Quality
60%
Does it follow best practices?
Impact
99%
0.99xAverage score across 6 eval scenarios
Optimize this skill with Tessl
npx tessl skill review --optimize ./backups/skills-batch-20251204-000554/plugins/testing/test-doubles-generator/skills/test-doubles-generator/SKILL.mdDiscovery
100%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 well-crafted skill description that excels across all dimensions. It provides specific concrete actions, includes natural trigger terms that developers would use, explicitly states both what the skill does and when to use it, and has a clear niche that distinguishes it from other skills. The inclusion of explicit slash commands further strengthens its distinctiveness.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple specific concrete actions: 'create mocks, stubs, spies, and fakes', 'analyzes dependencies', 'generates appropriate test doubles based on the chosen testing framework'. Also names specific frameworks (Jest, Sinon). | 3 / 3 |
Completeness | Clearly answers both what ('automatically create mocks, stubs, spies, and fakes', 'analyzes dependencies', 'generates test doubles based on testing framework') AND when ('when you need to generate test doubles... to isolate units of code during testing') with explicit trigger guidance including commands. | 3 / 3 |
Trigger Term Quality | Excellent coverage of natural terms users would say: 'test doubles', 'mocks', 'stubs', 'spies', 'fakes', 'unit testing', plus explicit commands '/gen-doubles' and '/gd'. These are terms developers naturally use when needing this functionality. | 3 / 3 |
Distinctiveness Conflict Risk | Clear niche focused specifically on test double generation with distinct triggers. The specific terminology (mocks, stubs, spies, fakes) and explicit commands ('/gen-doubles', '/gd') make it unlikely to conflict with general testing or code generation skills. | 3 / 3 |
Total | 12 / 12 Passed |
Implementation
20%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This skill content is largely descriptive rather than instructive, explaining concepts Claude already understands and describing what the skill does rather than providing actionable guidance. It lacks any executable code examples, concrete command syntax, or specific output formats. The content would benefit from being reduced to essential instructions with actual code snippets showing generated test doubles.
Suggestions
Replace the abstract 'Examples' section with actual executable code showing input code and the generated test double output for each framework (Jest, Sinon)
Add the exact command syntax for triggering the skill (e.g., `/gen-doubles <file> --framework jest --type mock`)
Remove the 'Overview', 'How It Works', and 'When to Use' sections entirely - this information is redundant with the skill description and wastes tokens
Add a concrete output format showing what the generated test double code looks like for a real dependency
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The content is verbose and explains concepts Claude already knows (what mocks, stubs, spies, and fakes are, when to use them). The 'Overview', 'How It Works', and 'When to Use' sections are largely redundant with the description and contain no actionable information. | 1 / 3 |
Actionability | No executable code, commands, or concrete examples are provided. The 'Examples' section describes what the skill 'will do' in abstract terms but provides no actual generated code, no command syntax, and no copy-paste ready snippets. | 1 / 3 |
Workflow Clarity | The 'How It Works' section lists a 3-step process, but it's abstract and lacks validation checkpoints. There's no guidance on what to do if generation fails or how to verify the generated doubles are correct. | 2 / 3 |
Progressive Disclosure | Content is organized into sections, but everything is inline with no references to external files. The structure is reasonable but the content itself is mostly filler that could be eliminated rather than split out. | 2 / 3 |
Total | 6 / 12 Passed |
Validation
81%Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.
Validation — 9 / 11 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
allowed_tools_field | 'allowed-tools' contains unusual tool name(s) | Warning |
frontmatter_unknown_keys | Unknown frontmatter key(s) found; consider removing or moving to metadata | Warning |
Total | 9 / 11 Passed | |
- Reviewed
Table of Contents
Is this your skill?
If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.