diff --git a/contracts/protocol/Sector3DAO.sol b/contracts/protocol/Sector3DAO.sol
index 316ff31..4eb3925 100644
--- a/contracts/protocol/Sector3DAO.sol
+++ b/contracts/protocol/Sector3DAO.sol
@@ -54,32 +54,34 @@ contract Sector3DAO {
     owner = owner_;
   }
 
+  modifier onlyOwner() {
+    require(msg.sender == owner, "You are not authorized to perform this action.");
+    _;
+  }
+
+
   /**
    * Updates the DAO's name.
    */
-  function setName(string calldata name_) public {
-    require(msg.sender == owner, "You aren't the owner");
+  function setName(string calldata name_) public onlyOwner {
     name = name_;
   }
 
   /**
    * Updates the DAO's purpose.
    */
-  function setPurpose(string calldata purpose_) public {
-    require(msg.sender == owner, "You aren't the owner");
+  function setPurpose(string calldata purpose_) public onlyOwner {    
     purpose = purpose_;
   }
 
   /**
    * Updates the DAO's token.
    */
-  function setToken(address token_) public {
-    require(msg.sender == owner, "You aren't the owner");
+  function setToken(address token_) public onlyOwner {
     token = token_;
   }
 
-  function deployPriority(string calldata title, address rewardToken, uint16 epochDurationInDays, uint256 epochBudget, address gatingNFT) public returns (Sector3DAOPriority) {
-    require(msg.sender == owner, "You aren't the owner");
+  function deployPriority(string calldata title, address rewardToken, uint16 epochDurationInDays, uint256 epochBudget, address gatingNFT) public onlyOwner returns (Sector3DAOPriority) {
     Sector3DAOPriority priority = new Sector3DAOPriority(address(this), title, rewardToken, epochDurationInDays, epochBudget, gatingNFT);
     priorities.push(priority);
     return priority;
@@ -89,8 +91,7 @@ contract Sector3DAO {
     return priorities;
   }
 
-  function removePriority(Sector3DAOPriority priority) public {
-    require(msg.sender == owner, "You aren't the owner");
+  function removePriority(Sector3DAOPriority priority) public onlyOwner {        
     Sector3DAOPriority[] memory prioritiesAfterRemoval = new Sector3DAOPriority[](priorities.length - 1);
     uint16 prioritiesIndex = 0;
     for (uint16 i = 0; i < prioritiesAfterRemoval.length; i++) {
@@ -102,4 +103,6 @@ contract Sector3DAO {
     }
     priorities = prioritiesAfterRemoval;
   }
+
+
 }
diff --git a/contracts/protocol/Sector3DAOFactory.sol b/contracts/protocol/Sector3DAOFactory.sol
index df77333..d17d5cf 100644
--- a/contracts/protocol/Sector3DAOFactory.sol
+++ b/contracts/protocol/Sector3DAOFactory.sol
@@ -9,11 +9,21 @@ contract Sector3DAOFactory {
 
   address[] public daos;
 
+  error YouAreNotAuthorized();
+
   constructor() {
     owner = msg.sender;
   }
 
-  function setOwner(address owner_) public {
+  
+
+  modifier onlyOwner() {
+    require(msg.sender == owner, "You are not authorized to perform this action.");
+    _;
+}
+
+
+  function setOwner(address owner_) public onlyOwner {
     require(msg.sender == owner, "You aren't the owner");
     owner = owner_;
   }
@@ -28,7 +38,7 @@ contract Sector3DAOFactory {
     return address(dao);
   }
 
-  function removeDAO(address dao) public {
+  function removeDAO(address dao) public onlyOwner {
     require(msg.sender == owner, "You aren't the owner");
     address[] memory daosAfterRemoval = new address[](daos.length - 1);
     uint16 daosIndex = 0;
diff --git a/contracts/protocol/Sector3DAOPriority.sol b/contracts/protocol/Sector3DAOPriority.sol
index edb31cf..52847c7 100644
--- a/contracts/protocol/Sector3DAOPriority.sol
+++ b/contracts/protocol/Sector3DAOPriority.sol
@@ -28,6 +28,7 @@ contract Sector3DAOPriority is IPriority {
   error NoRewardForEpoch();
   error RewardAlreadyClaimed();
   error NoGatingNFTOwnership();
+  error InvalidInput();
 
   constructor(address dao_, string memory title_, address rewardToken_, uint16 epochDurationInDays, uint256 epochBudget_, address gatingNFT_) {
     dao = dao_;
@@ -53,22 +54,27 @@ contract Sector3DAOPriority is IPriority {
    */
   function addContribution(string memory description, string memory proofURL, uint8 hoursSpent, uint8 alignmentPercentage) public {
     if (address(gatingNFT) != address(0x0)) {
-      if (gatingNFT.balanceOf(msg.sender) == 0) {
-        revert NoGatingNFTOwnership();
-      }
+        if (gatingNFT.balanceOf(msg.sender) == 0) {
+            revert NoGatingNFTOwnership();
+        }
+    }
+    if(bytes(description).length == 0 || bytes(proofURL).length == 0){
+        revert InvalidInput();
     }
+    uint16 epochIndex = getEpochIndex();
     Contribution memory contribution = Contribution({
-      timestamp: block.timestamp,
-      epochIndex: getEpochIndex(),
-      contributor: msg.sender,
-      description: description,
-      proofURL: proofURL,
-      hoursSpent: hoursSpent,
-      alignmentPercentage: alignmentPercentage
+        timestamp: block.timestamp,
+        epochIndex: epochIndex,
+        contributor: msg.sender,
+        description: description,
+        proofURL: proofURL,
+        hoursSpent: hoursSpent,
+        alignmentPercentage: alignmentPercentage
     });
     contributions.push(contribution);
     emit ContributionAdded(contribution);
-  }
+}
+
 
   function getContributions() public view returns (Contribution[] memory) {
     return contributions;
@@ -113,11 +119,12 @@ contract Sector3DAOPriority is IPriority {
     if (rewardClaimed) {
       revert RewardAlreadyClaimed();
     }
-    rewardToken.transfer(msg.sender, epochReward);
+
     claims[epochIndex][msg.sender] = true;
     claimsBalance += epochReward;
+    require(rewardToken.transfer(msg.sender, epochReward), "Reward transfer failed");
     emit RewardClaimed(epochIndex, msg.sender, epochReward);
-  }
+}
 
   /**
    * Calculates a contributor's token allocation of the budget for a given epoch.
@@ -129,13 +136,15 @@ contract Sector3DAOPriority is IPriority {
     return epochBudget * allocationPercentage / 100;
   }
 
-  /**
-   * Checks if a contributor's reward has been claimed for a given epoch.
+
+   /** 
+    * Checks if a contributor's reward has been claimed for a given epoch.
    */
   function isRewardClaimed(uint16 epochIndex, address contributor) public view returns (bool) {
     return claims[epochIndex][contributor];
   }
 
+
   /**
    * Calculates a contributor's percentage allocation of the budget for a given epoch.
    *