API Craft Pro — Instant API Mocker & Type Generator

Real-time XHR/Fetch interceptor, zero-config API response mocker, latency simulator, and instant TypeScript/Zod generator.

API Craft Pro is an all-in-one developer workbench built directly into Chrome's native SidePanel. It empowers frontend engineers, QA testers, and full-stack developers to inspect live network traffic, mock API responses without touching backend code, and generate TypeScript & Zod schemas in one click. 🚀 CORE FEATURES 1. 📡 Live XHR & Fetch Traffic Monitor • Automatically captures JSON API requests (window.fetch & XMLHttpRequest) in real time. • Inspect formatted Response JSON, Request Headers, Payloads, HTTP status codes, and response duration (ms) side-by-side with your web app. • Filter traffic instantly by URL path, HTTP method (GET, POST, PUT, PATCH, DELETE), or status code. 2. 🎭 Zero-Config API Mock Studio & Latency Simulator • Convert any captured live API request into an active Mock Rule with a single click. • Match endpoints by URL substring or Regular Expression (/regex/). • Simulate edge cases and error states (200, 201, 400, 401, 403, 404, 500) without waiting for backend changes. • Test loading skeletons and timeout handling with customizable network latency delays (0ms to 60,000ms). • Short-circuits matched requests directly in the browser—no real network request is sent when mocked. • Export and import project mock rule configurations as JSON files to share test scenarios with your team. 3. 🛠️ Instant Type & Code Generator (100% Local AST Engine) Transform any captured API response or custom JSON payload into production-ready code: • TypeScript Interfaces: Clean, deduplicated export interfaces with automatic optional property and union type inference. • Zod Validation Schemas: Complete z.object(...) runtime validation schemas with .nullable() and .optional() support. • JSON Schema (Draft-07): Standard Draft-07 JSON Schema for OpenAPI documentation or LLM structured outputs. • Typed Fetch Client Functions: Ready-to-use async fetch functions with complete TypeScript request/response type annotations. 🔒 PRIVACY-FIRST & LOCAL-ONLY ARCHITECTURE • 100% Local Processing: All API interception, JSON parsing, and code generation run entirely inside your browser. • Zero Data Collection: Your browsing activity, API headers, and response payloads never leave your device and are stored strictly in Chrome's local storage. • Multi-Language UI: Built-in support for English, Traditional Chinese (繁體中文), and Japanese (日本語).