diff --git a/contracts/OrderLib.sol b/contracts/OrderLib.sol
index 894631df..e0160ac8 100644
--- a/contracts/OrderLib.sol
+++ b/contracts/OrderLib.sol
@@ -8,7 +8,7 @@ import "@1inch/solidity-utils/contracts/libraries/AddressLib.sol";
 import "./interfaces/IOrderMixin.sol";
 import "./libraries/MakerTraitsLib.sol";
 import "./libraries/ExtensionLib.sol";
-import "./helpers/AmountCalculator.sol";
+import "./libraries/AmountCalculatorLib.sol";
 import "./interfaces/IAmountGetter.sol";
 
 /**
@@ -96,7 +96,7 @@ import "./interfaces/IAmountGetter.sol";
         bytes calldata data = extension.makingAmountData();
         if (data.length == 0) {
             // Linear proportion
-            return AmountCalculator.getMakingAmount(order.makingAmount, order.takingAmount, requestedTakingAmount);
+            return AmountCalculatorLib.getMakingAmount(order.makingAmount, order.takingAmount, requestedTakingAmount);
         }
         return IAmountGetter(address(bytes20(data))).getMakingAmount(
             order,
@@ -130,7 +130,7 @@ import "./interfaces/IAmountGetter.sol";
         bytes calldata data = extension.takingAmountData();
         if (data.length == 0) {
             // Linear proportion
-            return AmountCalculator.getTakingAmount(order.makingAmount, order.takingAmount, requestedMakingAmount);
+            return AmountCalculatorLib.getTakingAmount(order.makingAmount, order.takingAmount, requestedMakingAmount);
         }
         return IAmountGetter(address(bytes20(data))).getTakingAmount(
             order,
diff --git a/contracts/helpers/DutchAuctionCalculator.sol b/contracts/extensions/DutchAuctionCalculator.sol
similarity index 92%
rename from contracts/helpers/DutchAuctionCalculator.sol
rename to contracts/extensions/DutchAuctionCalculator.sol
index f331b88a..435f303b 100644
--- a/contracts/helpers/DutchAuctionCalculator.sol
+++ b/contracts/extensions/DutchAuctionCalculator.sol
@@ -5,6 +5,8 @@ pragma solidity 0.8.19;
 import "@openzeppelin/contracts/utils/math/Math.sol";
 import "../interfaces/IAmountGetter.sol";
 
+/// @title A helper that implements price decay over time from max to min
+/// @notice The contract implements Dutch auction price calculation for 1inch limit orders, it is used by 1inch Fusion
 contract DutchAuctionCalculator is IAmountGetter {
     using Math for uint256;
 
diff --git a/contracts/helpers/ERC1155Proxy.sol b/contracts/extensions/ERC1155Proxy.sol
similarity index 100%
rename from contracts/helpers/ERC1155Proxy.sol
rename to contracts/extensions/ERC1155Proxy.sol
diff --git a/contracts/helpers/ERC721Proxy.sol b/contracts/extensions/ERC721Proxy.sol
similarity index 100%
rename from contracts/helpers/ERC721Proxy.sol
rename to contracts/extensions/ERC721Proxy.sol
diff --git a/contracts/helpers/ERC721ProxySafe.sol b/contracts/extensions/ERC721ProxySafe.sol
similarity index 100%
rename from contracts/helpers/ERC721ProxySafe.sol
rename to contracts/extensions/ERC721ProxySafe.sol
diff --git a/contracts/helpers/ETHOrders.sol b/contracts/extensions/ETHOrders.sol
similarity index 97%
rename from contracts/helpers/ETHOrders.sol
rename to contracts/extensions/ETHOrders.sol
index 13e93fad..3d0c8924 100644
--- a/contracts/helpers/ETHOrders.sol
+++ b/contracts/extensions/ETHOrders.sol
@@ -9,7 +9,7 @@ import "@1inch/solidity-utils/contracts/OnlyWethReceiver.sol";
 import "../interfaces/IPostInteraction.sol";
 import "../OrderLib.sol";
 
-/// @title ETH limit orders contract
+/// @title Extension that will allow to create limit order that sell ETH. ETH must be deposited into the contract.
 contract ETHOrders is IPostInteraction, OnlyWethReceiver {
     using SafeERC20 for IWETH;
     using OrderLib for IOrderMixin.Order;
diff --git a/contracts/helpers/ImmutableOwner.sol b/contracts/extensions/ImmutableOwner.sol
similarity index 100%
rename from contracts/helpers/ImmutableOwner.sol
rename to contracts/extensions/ImmutableOwner.sol
diff --git a/contracts/helpers/OrderIdInvalidator.sol b/contracts/extensions/OrderIdInvalidator.sol
similarity index 100%
rename from contracts/helpers/OrderIdInvalidator.sol
rename to contracts/extensions/OrderIdInvalidator.sol
diff --git a/contracts/helpers/PrioirityFeeLimiter.sol b/contracts/extensions/PrioirityFeeLimiter.sol
similarity index 100%
rename from contracts/helpers/PrioirityFeeLimiter.sol
rename to contracts/extensions/PrioirityFeeLimiter.sol
diff --git a/contracts/helpers/RangeAmountCalculator.sol b/contracts/extensions/RangeAmountCalculator.sol
similarity index 100%
rename from contracts/helpers/RangeAmountCalculator.sol
rename to contracts/extensions/RangeAmountCalculator.sol
diff --git a/contracts/helpers/WethUnwrapper.sol b/contracts/extensions/WethUnwrapper.sol
similarity index 84%
rename from contracts/helpers/WethUnwrapper.sol
rename to contracts/extensions/WethUnwrapper.sol
index 8eedf8f8..86ae203e 100644
--- a/contracts/helpers/WethUnwrapper.sol
+++ b/contracts/extensions/WethUnwrapper.sol
@@ -6,6 +6,8 @@ import "@1inch/solidity-utils/contracts/OnlyWethReceiver.sol";
 import "@1inch/solidity-utils/contracts/interfaces/IWETH.sol";
 import "@1inch/solidity-utils/contracts/libraries/SafeERC20.sol";
 
+/// @title The extension to unwrap WETH and do payout in ETH in limit order postInteraction
+/// @notice The feature was embedded into TakerTraits, so it is obsolete and will be removed
 contract WethUnwrapper is OnlyWethReceiver {
     using SafeERC20 for IWETH;
 
diff --git a/contracts/helpers/AmountCalculator.sol b/contracts/libraries/AmountCalculatorLib.sol
similarity index 89%
rename from contracts/helpers/AmountCalculator.sol
rename to contracts/libraries/AmountCalculatorLib.sol
index aabd626b..3faa19cc 100644
--- a/contracts/helpers/AmountCalculator.sol
+++ b/contracts/libraries/AmountCalculatorLib.sol
@@ -2,8 +2,8 @@
 
 pragma solidity 0.8.19;
 
-/// @title A helper contract for calculations related to order amounts
-library AmountCalculator {
+/// @title The helper library to calculate linearly taker amount from maker amount and vice versa.
+library AmountCalculatorLib {
     /// @notice Calculates maker amount
     /// @return Result Floored maker amount
     function getMakingAmount(uint256 orderMakerAmount, uint256 orderTakerAmount, uint256 swapTakerAmount) internal pure returns(uint256) {