JI

Quickly generate N synthetic JSON fixtures based on a defined schema.

Install

mkdir -p .claude/skills/jimmy-testdata && curl -L -o skill.zip "https://agentskills.codes/api/skills/download/16485" && unzip -o skill.zip -d .claude/skills/jimmy-testdata && rm skill.zip

Installs to .claude/skills/jimmy-testdata

Activation

This is the description your AI agent reads to decide when to run this skill — the better it matches your request, the more reliably it fires.

Generate N synthetic test fixtures matching a user-defined schema — one Jimmy call per fixture, with optional edge-case mode for boundary and adversarial values.
161 chars · catalog descriptionno explicit “when” trigger
Beginner

Key capabilities

  • Generate N synthetic test fixtures
  • Match a user-defined schema for fixtures
  • Generate boundary and adversarial values for edge cases
  • Support various data types like string, int, email, url
  • Provide a summary of successful and failed fixture generations

How it works

The skill generates N fixtures by making one Jimmy call per fixture, using the provided schema and optionally generating edge-case values. It then compiles the results, including any parse failures.

Inputs & outputs

You give it
Schema (object mapping field names to types), number of fixtures (n), optional edge_case boolean, optional max_concurrent integer
You get back
JSON object with an array of fixtures and a summary of generation results

When to use jimmy-testdata

  • Generate user test objects
  • Seed development database
  • Create API contract payloads

About jimmy-testdata

Uses a schema to generate multiple test fixtures, including edge-case values. It is ideal for seeding databases or creating API request payloads.

Generate N synthetic test fixtures matching a user-defined schema — one Jimmy call per fixture, with optional edge-case mode for boundary and adversarial values.

When not to use it

  • When generating large nested object graphs
  • When generating exact values that need manual control
  • When generating relational data with foreign-key consistency constraints

Limitations

  • Schemas should be shallow (5-10 fields)
  • Expect a ~5-15% parse failure rate on complex schemas
  • No automatic retry on parse failure

How it compares

This skill automates the generation of multiple schema-compliant test fixtures, including edge cases, which is more efficient than manually creating each fixture.

Compared to similar skills

jimmy-testdata side by side with the closest alternatives in the catalog.

SkillInstallsUpdatedSafetyDifficulty
jimmy-testdata (this skill)04moNo flagsBeginner
vitest416moNo flagsIntermediate
svelte-expert119moNo flagsIntermediate
implementing-cards72moReviewAdvanced

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Example prompts that trigger this skill in your AI assistant.

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