x402 Payments Playground

Configure payment request parameters and run an end to end paid API call.

Documentation

Configuration

Amount in USD quoted for payment requirements.

Verifies and settles x402 payments on-chain.

Blockchain timestamp receipt

Pay from a different chain

Pay via on-chain ERC-20 transfer (gas-free on SKALE)

Give buyers free calls before payment

Health check before accepting payment

Auto-reject after repeated failures

Auto-credit on endpoint errors (5xx)

Inject live on-chain reputation into 402 response

Record successRate and responseTime on-chain after settlement

Fetch on-chain reputation from Solana and inject into 402 response

Record reputation on-chain via Solana MPL Core NFT program

Paid API Call
$0.01 USDC

Pay for access with USDC on Base.

API Call Response

Ready for a paid API request.

Use custom URL

Default playground endpoint: https://api.relai.fi/api/playground/premium?network=base&asset=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913&amountUsd=0.01&payTo=0x1892f72fdB3A966b2AD8595aA5f7741Ef72d6085&waitUntil=simulated&paymentScheme=exact

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