Spending limit

You can limit the amount of ERC20 tokens transferable through a session function. Attach the policy at the function level — it caps the cumulative amount across all uses of that function. Examples on this page use @rhinestone/sdk, where rhinestone is the RhinestoneSDK instance from Create a session with a custom setup.

import { erc20Abi, parseUnits } from "viem";
import { base } from "viem/chains";

const session = await rhinestone.createSession({
  chain: base,
  owners: {
    type: "ecdsa",
    accounts: [sessionOwnerAccount],
  },
  permissions: [
    {
      abi: erc20Abi,
      address: usdcAddress,
      functions: {
        transfer: {
          spendingLimit: {
            token: usdcAddress,
            amount: parseUnits("10", 6),
          },
        },
      },
    },
  ],
});

This caps total USDC transfers within the session to 10 USDC. For cross-chain transfers, cap the permit’s from leg with maxAmount instead.

Embedded wallet

Custom setup