api-tester

Generate REST and GraphQL API test cases with status expectations and assertions.

1|Updated Mar 6, 2026
One-click install
npx skills add https://github.com/kernex-dev/kernex-agent --skill api-tester-kernex-dev
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: api-tester
Source: https://github.com/kernex-dev/kernex-agent/tree/main/deploy/skills/api-tester
Command: npx skills add https://github.com/kernex-dev/kernex-agent --skill api-tester-kernex-dev

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Automated generation and validation of API tests to catch contract violations and surface coverage gaps.

Core Features & Use Cases

  • Generate end-to-end API test suites for REST and GraphQL endpoints, including happy-path, validation errors, auth failures, and state mutations.
  • Provide structured outputs with precise assertions, teardown guidance, and coverage gap reporting.
  • Prioritize deterministic testing workflows for headless agent environments and CI pipelines.

Quick Start

Provide a complete API test suite scaffold for REST and GraphQL endpoints given a surface description.

Frequently Asked Questions about api-tester

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I generate API tests for both REST and GraphQL endpoints?

To generate API tests, provide an API surface description including endpoints, methods, and auth schemes. The system identifies response shapes and generates exhaustive test cases across happy-path, validation errors, auth failures, and state-mutating scenarios for both REST and GraphQL.

What is failure-focused API testing and how does it catch contract violations?

Failure-focused API testing targets contract violations by generating test cases for validation errors, auth failures, and state mutations. It produces structured outputs with exact status expectations and precise field assertions while flagging coverage gaps in the API surface.

Can I use automated API tests in headless CI pipeline environments?

Yes, automated API tests prioritize deterministic testing workflows for headless agent environments and CI pipelines. They produce structured outputs with exact status expectations, precise field assertions, and teardown instructions to ensure reliable automated execution.

How do I identify API surfaces and auth schemes to inform test generation?

Identifying API surfaces involves analyzing endpoints, methods, auth schemes, and response shapes from a provided surface description. This analysis directly informs the generation of exhaustive test cases covering happy-path, validation errors, auth failures, and state-mutating scenarios.

What is the best way to cover state-mutating scenarios in API test suites?

Covering state-mutating scenarios requires generating test cases with exact status expectations, precise field assertions, and teardown instructions. This approach validates state changes while ensuring proper cleanup and flagging any coverage gaps in the API surface.

Does API test generation work without external testing framework dependencies?

Yes, API test generation works without external dependencies. It produces a complete test suite scaffold with structured outputs, precise assertions, and teardown guidance from a surface description, which can then be integrated into your preferred testing framework.