Developer sandbox / Try it

Test a sponsorship call

This sends a real pm_sponsorUserOperation request to the Tollbeam router with a sample UserOperation, straight from your browser. A successful result proves your key authenticates and routes on testnet. Submitting the operation on-chain additionally requires signing, which this widget deliberately does not do; the quickstart covers the full flow.

Sandbox API keySent only to the Tollbeam API as a Bearer header. Never stored by this page.

ChainSender (smart account)

Request that will be sent

POST https://api.tollbeam.com/v1/base-sepolia/rpc
Authorization: Bearer <your key>

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "pm_sponsorUserOperation",
  "params": [
    {
      "sender": "0x2B5a82247f0684C92d7A000B9F067D0598Ca543B",
      "nonce": "0x0",
      "initCode": "0x",
      "callData": "0x",
      "callGasLimit": "0x30000",
      "verificationGasLimit": "0x30000",
      "preVerificationGas": "0x10000",
      "maxFeePerGas": "0x3b9aca00",
      "maxPriorityFeePerGas": "0x3b9aca00",
      "paymasterAndData": "0x",
      "signature": "0x"
    }
  ]
}

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