Cross-chain permits

Cross-chain permits define the cross-chain bridging scope available to a session. Set them at the session level via crossChainPermits, not per function. Each entry allows source and destination legs and defines the limits the session has to stay within.

A permit restricts bridging authority; it does not enable the session on another chain. For a transaction that uses the account on several chains, also configure Multi-chain sessions.

Basic usage

Restrict a session to only bridge USDC from Base to Arbitrum: Examples on this page use @rhinestone/sdk, where rhinestone is the RhinestoneSDK instance from Create a session with a custom setup.

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

const usdcOnBase = "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913";
const usdcOnArbitrum = "0xaf88d065e77c8cC2239327C5EDb3A432268e5831";

const session = await rhinestone.createSession({
  chain: base,
  owners: {
    type: "ecdsa",
    accounts: [sessionOwnerAccount],
  },
  crossChainPermits: [
    {
      from: [{ chain: base, token: usdcOnBase }],
      to: [{ chain: arbitrum, token: usdcOnArbitrum }],
    },
  ],
});

Pass each token’s address on its corresponding chain. Pass a single leg or an array, and omit a side entirely to leave it unrestricted — the settlement-layer allowlist, deadlines, and recipient rules still apply.

Field	Description
`from`	Source chain + token (+ optional `maxAmount` cap). Omit for no source-token restriction.
`to`	Destination chain + token (+ optional `recipient` pin). Omit for no destination-token restriction.

Guardrails

Tighten a permit with optional bounds:

const usdcOnBase = "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913";
const usdcOnArbitrum = "0xaf88d065e77c8cC2239327C5EDb3A432268e5831";

const session = await rhinestone.createSession({
  chain: base,
  owners: {
    type: "ecdsa",
    accounts: [sessionOwnerAccount],
  },
  crossChainPermits: [
    {
      from: [
        { chain: base, token: usdcOnBase, maxAmount: parseUnits("100", 6) },
      ],
      to: [{ chain: arbitrum, token: usdcOnArbitrum }],
      validAfter: new Date("2026-01-01"),
      validUntil: new Date("2027-01-01"),
      fillDeadline: [{ chain: arbitrum, max: new Date("2027-01-01") }],
    },
  ],
});

maxAmount on a source leg caps how much of that token the session can pull (a spending limit).
validAfter / validUntil bound the permit deadline. Both accept a Date.
fillDeadline bounds the fill window per destination chain.

Recipient safety

By default a cross-chain permit enforces bridge-to-self on-chain: the destination recipient must be the smart account itself. This stops a leaked session key from routing funds to an attacker-controlled address. Opt out explicitly only when you need to bridge to a different recipient:

const usdcOnBase = "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913";
const usdcOnArbitrum = "0xaf88d065e77c8cC2239327C5EDb3A432268e5831";

const session = await rhinestone.createSession({
  chain: base,
  owners: {
    type: "ecdsa",
    accounts: [sessionOwnerAccount],
  },
  crossChainPermits: [
    {
      from: [{ chain: base, token: usdcOnBase }],
      to: [
        { chain: arbitrum, token: usdcOnArbitrum, recipient: payoutAddress },
      ],
      allowRecipientNotAccount: true,
    },
  ],
});

Settlement layers

A permit allows any supported settlement layer by default. Pass settlementLayers to narrow it to a subset:

const usdcOnBase = "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913";
const usdcOnArbitrum = "0xaf88d065e77c8cC2239327C5EDb3A432268e5831";

const session = await rhinestone.createSession({
  chain: base,
  owners: {
    type: "ecdsa",
    accounts: [sessionOwnerAccount],
  },
  crossChainPermits: [
    {
      from: [{ chain: base, token: usdcOnBase }],
      to: [{ chain: arbitrum, token: usdcOnArbitrum }],
      settlementLayers: ["ECO"],
    },
  ],
});

In @rhinestone/sdk 2.16.1, "ECO" authorizes only the legacy Standard ECO arbiters. Eco solver-network routes use a different adapter and are intentionally blocked because the built-in claim policy cannot yet verify their encoded destination, token, recipient, and deadline. A quote that requires a solver-network ECO route cannot use this session; use another supported settlement layer or the account owner until route-aware authorization is available.

Embedded wallet

Custom setup

Basic usage

Guardrails

Recipient safety

Settlement layers

​Basic usage

​Guardrails

​Recipient safety

​Settlement layers

Basic usage

Guardrails

Recipient safety

Settlement layers