Send Manager Precompile

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "./interfaces/ISendManagerPrecompile.sol";

contract TokenSender {
    ISendManagerPrecompile constant SENDMANAGER =
        ISendManagerPrecompile(0x0000000000000000000000000000000000001003);

    function sendCoins(
        string memory toAddress,
        string memory denom,
        uint256 amount
    ) external returns (bool) {
        string memory msgJson = string(abi.encodePacked(
            '{"to_address":"', toAddress,
            '","amount":[{"denom":"', denom,
            '","amount":"', _uintToString(amount), '"}]}'
        ));

        return SENDMANAGER.send(msgJson);
    }

    function _uintToString(uint256 value) internal pure returns (string memory) {
        if (value == 0) return "0";
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) { digits++; temp /= 10; }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }
}

import { ethers } from "ethers";

const SENDMANAGER_ADDRESS = "0x0000000000000000000000000000000000001003";

const sendManagerABI = [
  "function send(string memory msgJson) external returns (bool success)"
];

const sendManager = new ethers.Contract(SENDMANAGER_ADDRESS, sendManagerABI, signer);

const msgJson = JSON.stringify({
  to_address: "bb1py4mfpg6uf59qkyzg0nmau322c5873eeysp5ue",
  amount: [{ denom: "ubadge", amount: "1000000000" }]
});

const tx = await sendManager.send(msgJson);
await tx.wait();

interface ISendManagerPrecompile {
    /// @notice Send native Cosmos coins from the caller to a recipient
    /// @param msgJson JSON string matching MsgSendWithAliasRouting protobuf format
    /// @return success Whether the send succeeded
    function send(string memory msgJson) external returns (bool success);
}

{
  "to_address": "bb1py4mfpg6uf59qkyzg0nmau322c5873eeysp5ue",
  "amount": [
    {"denom": "ubadge", "amount": "1000000000"},
    {"denom": "badgeslp:64:utoken", "amount": "5"}
  ]
}