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Unibase Docs

Unibase Pay Quick Start

1. Base URL

Section titled “1. Base URL”
https://api.x402.unibase.com/v2

2. Check the facilitator is up

Section titled “2. Check the facilitator is up”

There is no /health endpoint. GET /supported doubles as a liveness probe and tells you what the facilitator currently accepts:

Terminal window
curl https://api.x402.unibase.com/v2/supported

3. Endpoints

Section titled “3. Endpoints”
Method Endpoint Description
POST /verify Check a payment payload without settling it
POST /settle Settle a payment on-chain
GET /supported Scheme and network pairs served

/verify and /settle are POST only.

4. Protocol Flow

Section titled “4. Protocol Flow”
  1. Server returns 402 with its payment requirements
  2. Client signs a payment payload and retries
  3. Server calls /verify, serves the resource, then calls /settle

5. What V2 supports

Section titled “5. What V2 supports”
  • Networks — BNB Smart Chain, BSC Testnet, Base, Base Sepolia, Polygon, Arbitrum One
  • Schemes — exact (fixed amount), upto (metered, settle actual usage), batch-settlement (many micropayments, one transaction)
  • Assets — ERC-20 via Permit2; EIP-3009 gasless transfers

Read GET /supported at runtime rather than hardcoding this list.

Next Steps

Section titled “Next Steps”