Skip to main content

​
What is ActumX?

ActumX is a SaaS platform that enables developers to monetize their APIs using the x402 payment protocol. Instead of building custom billing systems, ActumX provides a standardized way for APIs to request payments using HTTP 402 status codes, allowing clients to settle and retry requests automatically. The x402 protocol makes payment requirements machine-readable, eliminating the need for custom per-API billing logic. When your API requires payment, it responds with HTTP 402 and structured payment details. Clients can then settle the payment and retry with proof of payment - all handled programmatically.

Quick Start

Get started with ActumX in minutes - create an agent, generate an API key, and make your first paid request.

Architecture

Understand how ActumX works under the hood and how the x402 payment flow operates.

x402 Protocol

Learn about the x402 payment protocol and how it enables automated API monetization.

API Reference

Explore the complete API documentation with endpoints for agents, billing, and x402 transactions.

​
Key Features

​
Agent Management

Create and manage Solana-based agents (wallets) that can interact with the x402 payment system. Each agent has its own public/private key pair for handling blockchain transactions. 
curl -X POST https://api.actumx.app/v1/agents \
  -H "Cookie: better-auth.session_token=YOUR_SESSION" \
  -H "Content-Type: application/json" \
  -d '{"name": "My First Agent"}'

​
API Key Authentication

Generate API keys to authenticate requests to protected endpoints. API keys are hashed and stored securely, with only the prefix visible for identification. 
curl -X POST https://api.actumx.app/v1/api-keys \
  -H "Cookie: better-auth.session_token=YOUR_SESSION" \
  -H "Content-Type: application/json" \
  -d '{"name": "Production Key"}'

​
Credit-Based Billing

Top up your account with credits (in cents) to pay for API requests. The platform maintains a credit ledger tracking all debits and credits.
Current pricing: $0.25 per paid request to the /v1/protected/quote endpoint

​
x402 Payment Flow

The x402 protocol enables a three-step payment flow:
  1. Challenge: Request a protected endpoint without payment proof, receive HTTP 402 with payment details
  2. Settlement: Submit payment to the settlement endpoint, receive a receipt
  3. Retry: Retry the original request with payment ID and receipt proof
1

Initial Request

Make a request to a protected endpoint like /v1/protected/quote
2

Receive Payment Challenge

Get HTTP 402 response with payment details including amount, payment ID, and settlement endpoint
3

Settle Payment

POST to /v1/x402/settle with the payment ID to deduct credits and receive a receipt
4

Complete Request

Retry original request with x-payment-id and x-payment-proof headers to access the protected resource

​
Transaction Tracking

Every x402 transaction is tracked with detailed status information:
  • pending: Payment challenge issued, awaiting settlement
  • settled: Payment settled, receipt issued, awaiting consumption
  • completed: Request completed successfully with payment proof

​
MCP Integration

ActumX provides an MCP (Model Context Protocol) server for AI agent integration. The MCP endpoint supports tool calls like checking wallet balances directly from AI assistants. 
curl -X POST https://api.actumx.app/mcp \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "wallet_balance",
      "arguments": {"agentId": "agent_abc123"}
    }
  }'

​
Why x402?

Traditional API monetization requires:
  • Custom billing integration for each API
  • Complex subscription management
  • Manual payment reconciliation
  • Vendor-specific SDKs
With x402:
  • ✅ Standardized payment protocol
  • ✅ Machine-readable payment requirements
  • ✅ Automatic retry logic
  • ✅ Pay-per-use pricing
  • ✅ No subscription overhead

​
Technology Stack

Backend

Elysia HTTP server on Bun runtime with Drizzle ORM and PostgreSQL

Frontend

Next.js (App Router) with shadcn/ui components and Tailwind CSS

Authentication

Better Auth for secure session management with email/password authentication

Blockchain

Solana integration via @solana/web3.js for agent wallet management

​
Next Steps

Get Started

Follow the quickstart guide

Learn Concepts

Understand x402 protocol

Explore API

Browse API endpoints