Installation

The RefundKit SDK is distributed as @refundkit/sdk on npm. It supports both ESM and CommonJS and ships with full TypeScript type definitions.

Package Managers

Install with your preferred package manager:

# npm
npm install @refundkit/sdk

# pnpm
pnpm add @refundkit/sdk

# yarn
yarn add @refundkit/sdk

Module System Support

The SDK ships dual-format builds. Your bundler or runtime will automatically resolve the correct format.

ESM (import):

import RefundKit from '@refundkit/sdk';

const rk = new RefundKit({ apiKey: process.env.REFUNDKIT_API_KEY! });

CommonJS (require):

const { default: RefundKit } = require('@refundkit/sdk');

const rk = new RefundKit({ apiKey: process.env.REFUNDKIT_API_KEY });

The package.json exports map handles resolution:

{
  ".": {
    "types": "./dist/index.d.ts",
    "import": "./dist/index.js",
    "require": "./dist/index.cjs"
  },
  "./mcp": {
    "types": "./dist/mcp/index.d.ts",
    "import": "./dist/mcp/index.js",
    "require": "./dist/mcp/index.cjs"
  }
}

MCP Server Subpath

The MCP server is available as a separate export path. This allows you to import it without pulling in the full SDK if you only need the server:

import { createMcpServer, startMcpServer } from '@refundkit/sdk/mcp';

CLI Binary

The package also registers a refundkit binary that starts the MCP server. After installing globally or using npx:

# Via npx (no global install needed)
REFUNDKIT_API_KEY=rk_test_xxx npx @refundkit/sdk

# Via global install
npm install -g @refundkit/sdk
REFUNDKIT_API_KEY=rk_test_xxx refundkit

Runtime Requirements

Node.js: 18.0.0 or later (uses native fetch and crypto)
TypeScript: 5.0 or later (recommended for full type inference)
Browser: Not supported. The SDK uses Node.js crypto for API key utilities and is intended for server-side use.

Dependencies

The SDK has three runtime dependencies:

| Package | Purpose | |---------|---------| | zod | Input validation for all SDK methods | | stripe | Stripe payment processor integration | | @modelcontextprotocol/sdk | MCP server implementation |

These are managed automatically by your package manager.

Verifying Installation

After installation, verify the SDK is working:

import RefundKit, { getApiKeyEnvironment } from '@refundkit/sdk';

// Check key format
const env = getApiKeyEnvironment(process.env.REFUNDKIT_API_KEY!);
console.log('Environment:', env); // 'test' or 'live'

// Initialize client
const rk = new RefundKit({ apiKey: process.env.REFUNDKIT_API_KEY! });

// List refunds (should return empty array for new accounts)
const { data, error } = await rk.refunds.list();
if (error) {
  console.error('Connection failed:', error.message);
} else {
  console.log('Connected! Found', data.length, 'refunds.');
}

Next Steps

Configuration -- Configure base URL, timeouts, and other options.
Refunds -- Start creating and managing refunds.