API Mock Server Skill

SkillDev tools

This pack lets your AI create a mock API from an OpenAPI spec, a standard file that describes how an API works. Once added, your AI can turn that definition into fake endpoints you can test against. The result is a way to check your work without pointing it at the real API.

Use API Mock Server Skill in Claude, ChatGPT or Ahel Desktop

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Then ask your AI: use the API Mock Server Skill

Details

Instructions available. Your AI can read the instructions. Execution depends on the setup they require.

Account requirements not reviewed. Check the skill instructions before use; Ahel provides instructions and does not run this skill.

No other account needed.

After adding the pack, share an OpenAPI spec with your AI and ask it to create a mock API from it. Then point your tests at the mock it builds.

API Mock Server SkillStart free

What your AI can do with it

Create a mock API from an OpenAPI spec
Generate fake endpoints that follow your API definition
Test your work against a mock instead of the real API
Build a fresh mock whenever you need one for testing

What this skill tells your AI

The instructions your AI receives, as published by a5c-ai/babysitter in library/specializations/software-architecture/skills/api-mock-server/SKILL.md and read by Ahel’s review.

Overview

Generates and runs mock API servers from OpenAPI specifications with dynamic response generation, request validation, and Prism/Mockoon integration.

Capabilities

Generate mock server from OpenAPI spec
Dynamic response generation based on schemas
Request validation against spec
Prism and Mockoon integration
Custom response scenarios
Callback and webhook simulation
Stateful mock behavior

Target Processes

api-design-specification
microservices-decomposition

Input Schema

{
  "type": "object",
  "required": ["specPath"],
  "properties": {
    "specPath": {
      "type": "string",
      "description": "Path to OpenAPI specification"
    },
    "port": {
      "type": "number",
      "default": 4010
    },
    "engine": {
      "type": "string",
      "enum": ["prism", "mockoon", "custom"],
      "default": "prism"
    },
    "options": {
      "type": "object",
      "properties": {
        "dynamic": {
          "type": "boolean",
          "default": true,
          "description": "Generate dynamic responses"
        },
        "validateRequest": {
          "type": "boolean",
          "default": true
        },
        "cors": {
          "type": "boolean",
          "default": true
        },
        "scenarios": {
          "type": "array",
          "description": "Custom response scenarios"
        }
      }
    }
  }
}

Output Schema

{
  "type": "object",
  "properties": {
    "serverUrl": {
      "type": "string"
    },
    "port": {
      "type": "number"
    },
    "endpoints": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "method": { "type": "string" },
          "path": { "type": "string" }
        }
      }
    },
    "pid": {
      "type": "number",
      "description": "Process ID of running server"
    }
  }
}

Usage Example

{
  kind: 'skill',
  skill: {
    name: 'api-mock-server',
    context: {
      specPath: 'api/openapi.yaml',
      port: 4010,
      engine: 'prism',
      options: {
        dynamic: true,
        validateRequest: true
      }
    }
  }
}

Signals

GitHub stars: 2k
Forks: 113
Last commit: Sep 2026

Advanced

Item type: skill
Key: api-mock-server
Source: github.com/a5c-ai/babysitter

github.com/a5c-ai/babysitter