How do I check if an account has opted in to direct transfer?

On Aptos, the primary way to send a Token is in two phases, an offer by the sender and then an accept by the recipient. However, if users opt in to allowing direct transfer, the sender can just send that recipient an NFT in a single transaction. How do I check if a user has opted in to direct transfer?

You can tell if an account has opted-in to direct transfer by looking at the 0x3::token::TokenStore resource on their account. For example, using curl:

curl https://fullnode.mainnet.aptoslabs.com/v1/accounts/0x232098630cfad4734812fa37dc18d9b8d59242feabe49259e26318d468a99584/resource/0x3::token::TokenStore

This curl above means "get me the 0x3::token::TokenStore resource on account 0x232098630cfad4734812fa37dc18d9b8d59242feabe49259e26318d468a99584.

The output (run through jq):

{
  "type": "0x3::token::TokenStore",
  "data": {
    "burn_events": {
      "counter": "0",
      "guid": {
        "id": {
          "addr": "0x232098630cfad4734812fa37dc18d9b8d59242feabe49259e26318d468a99584",
          "creation_num": "6"
        }
      }
    },
    "deposit_events": {
      "counter": "6",
      "guid": {
        "id": {
          "addr": "0x232098630cfad4734812fa37dc18d9b8d59242feabe49259e26318d468a99584",
          "creation_num": "4"
        }
      }
    },
    "direct_transfer": true,
    "mutate_token_property_events": {
      "counter": "1",
      "guid": {
        "id": {
          "addr": "0x232098630cfad4734812fa37dc18d9b8d59242feabe49259e26318d468a99584",
          "creation_num": "7"
        }
      }
    },
    "tokens": {
      "handle": "0x91744f237fa81aedf45199a8c2bd568e7e329e48e02ae82786632fd0ebd3ad01"
    },
    "withdraw_events": {
      "counter": "0",
      "guid": {
        "id": {
          "addr": "0x232098630cfad4734812fa37dc18d9b8d59242feabe49259e26318d468a99584",
          "creation_num": "5"
        }
      }
    }
  }
}

If direct_transfer is true, then they have opted-in to direct transfer.

Using the TS SDK it would look like this:

const client = new AptosClient(NODE_URL);

const resource = await client.getAccountResource(
    accountAddress,
    "0x3::token::TokenStore",
);

const hasOptedIn = (resource.data as any)["direct_transfer"]

If you get a 404 when trying to retrieve the 0x3::token::TokenStore, it also implies that they haven't opted in to direct transfer, since they've never interacted with tokens.