docs: utils

contracts/utils/AccessControl.sol

@@ -3,6 +3,12 @@ pragma solidity 0.8.7;
 
 import "./Ownable.sol";
 
+/**
+ * @title AccessControl
+ * @dev This abstract contract implements access control mechanism based on roles.
+ * Each role can have one or more addresses associated with it, which are granted
+ * permission to execute functions with the onlyRole modifier.
+ */
 abstract contract AccessControl is Ownable {
     // role => address => permit
     mapping(bytes32 => mapping(address => bool)) private _permits;

contracts/utils/Hasher.sol

@@ -3,6 +3,10 @@ pragma solidity 0.8.7;
 
 import "../interfaces/IHasher.sol";
 
+/**
+ * @title Hasher
+ * @notice contract for hasher contract that calculates the packed message
+ */
 contract Hasher is IHasher {
     /// @inheritdoc IHasher
     function packMessage(

contracts/utils/Ownable.sol

@@ -1,6 +1,11 @@
 // SPDX-License-Identifier: GPL-3.0-only
 pragma solidity 0.8.7;
 
+/**
+ * @title Ownable
+ * @dev The Ownable contract provides a simple way to manage ownership of a contract
+ * and allows for ownership to be transferred to a nominated address.
+ */
 abstract contract Ownable {
     address private _owner;
     address private _nominee;
@@ -11,34 +16,62 @@ abstract contract Ownable {
     error OnlyOwner();
     error OnlyNominee();
 
+    /**
+     * @dev Sets the contract's owner to the address that deploys the contract.
+     */
     constructor(address owner_) {
         _claimOwner(owner_);
     }
 
+    /**
+     * @dev Modifier that restricts access to only the contract's owner.
+     * Throws an error if the caller is not the owner.
+     */
     modifier onlyOwner() {
         if (msg.sender != _owner) revert OnlyOwner();
         _;
     }
 
+    /**
+     * @dev Returns the current owner of the contract.
+     */
     function owner() external view returns (address) {
         return _owner;
     }
 
+    /**
+     * @dev Returns the current nominee for ownership of the contract.
+     */
     function nominee() external view returns (address) {
         return _nominee;
     }
 
+    /**
+     * @dev Allows the current owner to nominate a new owner for the contract.
+     * Throws an error if the caller is not the owner.
+     * Emits an `OwnerNominated` event with the address of the nominee.
+     */
     function nominateOwner(address nominee_) external {
         if (msg.sender != _owner) revert OnlyOwner();
         _nominee = nominee_;
         emit OwnerNominated(_nominee);
     }
 
+    /**
+     * @dev Allows the nominated owner to claim ownership of the contract.
+     * Throws an error if the caller is not the nominee.
+     * Sets the nominated owner as the new owner of the contract.
+     * Emits an `OwnerClaimed` event with the address of the new owner.
+     */
     function claimOwner() external {
         if (msg.sender != _nominee) revert OnlyNominee();
         _claimOwner(msg.sender);
     }
 
+    /**
+     * @dev Internal function that sets the owner of the contract to the specified address
+     * and sets the nominee to address(0).
+     */
     function _claimOwner(address claimer_) internal {
         _owner = claimer_;
         _nominee = address(0);

contracts/utils/SignatureVerifier.sol

@@ -4,6 +4,10 @@ pragma solidity 0.8.7;
 import "../interfaces/ISignatureVerifier.sol";
 import "../libraries/SignatureVerifierLib.sol";
 
+/**
+ * @title Signature Verifier
+ * @notice Verifies the signatures and returns the address of signer recovered from the input signature or digest.
+ */
 contract SignatureVerifier is ISignatureVerifier {
     /// @inheritdoc ISignatureVerifier
     function recoverSigner(