APPD
Hardby xEcho AI

xEcho

Distinguished by unique on-chain settlement callbacks enabling post-payment programmability. Pioneered the 'Pay to X' concept including pay-to-earn and outcome-based payments. Built-in KYT/OFAC compliance screening for regulated use cases.

Last researched: 2026-03-30

Supported Chains

Base

Pricing

Free

0% fee on Base

Free

SDKs & Libraries

JavaScript / TypeScript

Standard x402 middleware compatible

Setup Steps

  1. 1
    Configure standard x402 middleware with xEcho facilitator URL
  2. 2
    Set up settlement callback endpoint for post-payment logic
  3. 3
    Configure KYT/OFAC compliance parameters if needed
  4. 4
    Implement Pay-to-X logic for outcome-based payments
  5. 5
    Test on Base with USDC

Use Cases

Pros & Cons

Pros

  • +Unique settlement callbacks for post-payment programmability
  • +Innovative Pay-to-X concept (pay-to-earn, outcome-based)
  • +KYT/OFAC compliance screening built-in
  • +0% fee on Base

Cons

  • -Very limited public documentation
  • -Base chain only
  • -No public GitHub repository
  • -No dedicated SDK (relies on standard x402 middleware)

Links