comment updates

contracts/src/TeleporterTokenDestination.sol

@@ -34,7 +34,10 @@ abstract contract TeleporterTokenDestination is
     /// @notice The ERC20 token this contract uses to pay for Teleporter fees.
     address public immutable feeTokenAddress;
 
-    /// @notice Required gas limit for sending tokens back to the source blockchain.
+    /**
+     * @notice Fixed gas cost for performing a multihop transfer on the `sourceBlockchainID`
+     * , before forwarding to the final destination bridge instance.
+     */
     uint256 public constant MULTIHOP_REQUIRED_GAS = 220_000;
 
     /**

contracts/src/interfaces/ITeleporterTokenBridge.sol

@@ -19,7 +19,9 @@ import {ITeleporterReceiver} from "@teleporter/ITeleporterReceiver.sol";
  * @param recipient address of the recipient on the destination chain
  * @param primaryFee amount of tokens to pay for Teleporter fee on the source chain
  * @param secondaryFee amount of tokens to pay for Teleporter fee if a multihop is needed
- * @param requiredGasLimit gas limit requirement for sending to a destination token bridge
+ * @param requiredGasLimit gas limit requirement for sending to a token bridge.
+ * This is required because the gas requirement varies based on the token bridge instance
+ * specified by `destinationBlockchainID` and `destinationBridgeAddress`.
  */
 struct SendTokensInput {
     bytes32 destinationBlockchainID;