update contract doc comments

solidity/src/MaybeMintERC721.sol

@@ -6,12 +6,14 @@ import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
 
 /**
  * @title MaybeMintERC721
- * @dev Mint ERC721 tokens for a fee in ERC20 tokens
+ * @dev Mint ERC721 tokens for a fee in ERC20 tokens. As this simple token is intended for
+ *      demonstration of batched EVM calls on Flow EVM using a single Cadence transaction, the
+ *      minting process is random and has some chance of failure.
  */
 contract MaybeMintERC721 is ERC721, Ownable {
     IERC20 public denomination;
     uint256 public mintCost;
-    address beneficiary;
+    address public beneficiary;
     uint256 public totalSupply;
 
     event MintCostUpdated(uint256 newCost);
@@ -33,28 +35,34 @@ contract MaybeMintERC721 is ERC721, Ownable {
     }
 
     /**
-     * @dev Mint a new ERC721 token to the caller. This contract must be approved to transfer mintCost amount from the caller
-     *      before minting the ERC721 to pay for mint
+     * @dev Mint a new ERC721 token to the caller with some chance of failure. This is for
+     *      demonstration purposes, intended to showcase how a single Cadence transaction can batch
+     *      multiple EVM calls and condition final execution based on the result of any individual
+     *      EVM call.
+     *
+     *      NOTE: This contract address must be approved to transfer mintCost amount from the caller
+     *      to the beneficiary before minting the ERC721 to pay for mint
      */
     function mint() external {
         // TODO: Get a random number to determine if the mint is successful
+        // TODO: Set token URI
         totalSupply++; // increment the total supply
         denomination.transferFrom(msg.sender, beneficiary, mintCost); // take payment for mint
         _mint(msg.sender, totalSupply); // mint the token, assigning the next tokenId
     }
 
     /**
      * @dev Set the cost to mint a new ERC721 token
-     * @param _mintCost The new cost to mint a token in the denomination ERC20 token
+     * @param _mintCost The new cost to mint a token in the denomination IERC20 token
      */
     function setMintCost(uint256 _mintCost) external onlyOwner {
         mintCost = _mintCost;
         emit MintCostUpdated(_mintCost);
     }
 
     /**
-     * @dev Set the ERC20 token to use as the denomination
-     * @param _denomination The address of the ERC20 token to use as the denomination
+     * @dev Set the IERC20 contract to use as the denomination
+     * @param _denomination The IERC20 contract address to use as the denomination for mint fee
      */
     function setDenomination(address _denomination) external onlyOwner {
         require(_denomination != address(0), "Denomination cannot be the zero address");
@@ -64,7 +72,7 @@ contract MaybeMintERC721 is ERC721, Ownable {
     }
 
     /**
-     * @dev Set the address to receive the minting fees
+     * @dev Set the address to receive the IERC20 token paid for minting fees
      * @param _beneficiary The address to receive the minting fees
      */
     function setBeneficiary(address _beneficiary) external onlyOwner {