diff --git a/packages/contracts-core/contracts/Destination.sol b/packages/contracts-core/contracts/Destination.sol
index 158d61459b..95b90d9e58 100644
--- a/packages/contracts-core/contracts/Destination.sol
+++ b/packages/contracts-core/contracts/Destination.sol
@@ -8,6 +8,7 @@ import {AGENT_ROOT_OPTIMISTIC_PERIOD} from "./libs/Constants.sol";
 import {IndexOutOfRange, NotaryInDispute, OutdatedNonce} from "./libs/Errors.sol";
 import {ChainGas, GasData} from "./libs/stack/GasData.sol";
 import {AgentStatus, DestinationStatus} from "./libs/Structures.sol";
+import {ChainContext} from "./libs/ChainContext.sol";
 // ═════════════════════════════ INTERNAL IMPORTS ══════════════════════════════
 import {AgentSecured} from "./base/AgentSecured.sol";
 import {DestinationEvents} from "./events/DestinationEvents.sol";
@@ -78,7 +79,7 @@ contract Destination is ExecutionHub, DestinationEvents, InterfaceDestination {
         if (localDomain != synapseDomain) {
             _nextAgentRoot = agentRoot;
             InterfaceLightManager(address(agentManager)).setAgentRoot(agentRoot);
-            destStatus.agentRootTime = uint40(block.timestamp);
+            destStatus.agentRootTime = ChainContext.blockTimestamp();
         }
         // No need to do anything on Synapse Chain, as the agent root is set in BondingManager
     }
@@ -198,12 +199,12 @@ contract Destination is ExecutionHub, DestinationEvents, InterfaceDestination {
     {
         status = destStatus;
         // Update the timestamp for the latest snapshot root
-        status.snapRootTime = uint40(block.timestamp);
+        status.snapRootTime = ChainContext.blockTimestamp();
         // No need to save agent roots on Synapse Chain, as they could be accessed via BondingManager
         // Don't update agent root, if there is already a pending one
         // Update the data for latest agent root only if it differs from the saved one
         if (localDomain != synapseDomain && !rootPending && _nextAgentRoot != agentRoot) {
-            status.agentRootTime = uint40(block.timestamp);
+            status.agentRootTime = ChainContext.blockTimestamp();
             status.notaryIndex = notaryIndex;
             _nextAgentRoot = agentRoot;
             emit AgentRootAccepted(agentRoot);
@@ -224,7 +225,7 @@ contract Destination is ExecutionHub, DestinationEvents, InterfaceDestination {
             if (GasData.unwrap(gasData) == GasData.unwrap(storedGasData.gasData)) continue;
             // Save the gas data
             _storedGasData[domain] =
-                StoredGasData({gasData: gasData, notaryIndex: notaryIndex, submittedAt: uint40(block.timestamp)});
+                StoredGasData({gasData: gasData, notaryIndex: notaryIndex, submittedAt: ChainContext.blockTimestamp()});
         }
     }
 }
diff --git a/packages/contracts-core/contracts/Summit.sol b/packages/contracts-core/contracts/Summit.sol
index f1ca2b0fc4..57f6a2de8a 100644
--- a/packages/contracts-core/contracts/Summit.sol
+++ b/packages/contracts-core/contracts/Summit.sol
@@ -10,6 +10,7 @@ import {Receipt, ReceiptLib} from "./libs/memory/Receipt.sol";
 import {Snapshot, SnapshotLib} from "./libs/memory/Snapshot.sol";
 import {AgentFlag, AgentStatus, DisputeFlag, MessageStatus} from "./libs/Structures.sol";
 import {Tips, TipsLib} from "./libs/stack/Tips.sol";
+import {ChainContext} from "./libs/ChainContext.sol";
 // ═════════════════════════════ INTERNAL IMPORTS ══════════════════════════════
 import {AgentSecured} from "./base/AgentSecured.sol";
 import {SummitEvents} from "./events/SummitEvents.sol";
@@ -276,7 +277,7 @@ contract Summit is SnapshotHub, SummitEvents, InterfaceSummit {
             pending: true,
             tipsAwarded: savedRcpt.tipsAwarded,
             receiptNotaryIndex: rcptNotaryIndex,
-            submittedAt: uint40(block.timestamp)
+            submittedAt: ChainContext.blockTimestamp()
         });
         // Save receipt tips
         _receiptTips[messageHash] = ReceiptTips({
diff --git a/packages/contracts-core/contracts/base/MessagingBase.sol b/packages/contracts-core/contracts/base/MessagingBase.sol
index b0785c1075..10d0021dab 100644
--- a/packages/contracts-core/contracts/base/MessagingBase.sol
+++ b/packages/contracts-core/contracts/base/MessagingBase.sol
@@ -1,6 +1,8 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
+// ══════════════════════════════ LIBRARY IMPORTS ══════════════════════════════
+import {ChainContext} from "../libs/ChainContext.sol";
 // ═════════════════════════════ INTERNAL IMPORTS ══════════════════════════════
 import {MultiCallable} from "./MultiCallable.sol";
 import {Versioned} from "./Version.sol";
@@ -27,8 +29,7 @@ abstract contract MessagingBase is MultiCallable, Versioned, Ownable2StepUpgrade
     uint256[50] private __GAP; // solhint-disable-line var-name-mixedcase
 
     constructor(string memory version_, uint32 synapseDomain_) Versioned(version_) {
-        // TODO: do we want to/need to check for overflow?
-        localDomain = uint32(block.chainid);
+        localDomain = ChainContext.chainId();
         synapseDomain = synapseDomain_;
     }
 
diff --git a/packages/contracts-core/contracts/events/StatementInboxEvents.sol b/packages/contracts-core/contracts/events/StatementInboxEvents.sol
index a5888509da..99abf8da93 100644
--- a/packages/contracts-core/contracts/events/StatementInboxEvents.sol
+++ b/packages/contracts-core/contracts/events/StatementInboxEvents.sol
@@ -36,7 +36,7 @@ abstract contract StatementInboxEvents {
      * @param attPayload    Raw payload with Attestation data for snapshot
      * @param attSignature  Notary signature for the attestation
      */
-    event InvalidStateWithAttestation(uint256 stateIndex, bytes statePayload, bytes attPayload, bytes attSignature);
+    event InvalidStateWithAttestation(uint8 stateIndex, bytes statePayload, bytes attPayload, bytes attSignature);
 
     /**
      * @notice Emitted when a proof of invalid state in the signed snapshot is submitted.
@@ -44,7 +44,7 @@ abstract contract StatementInboxEvents {
      * @param snapPayload   Raw payload with snapshot data
      * @param snapSignature Agent signature for the snapshot
      */
-    event InvalidStateWithSnapshot(uint256 stateIndex, bytes snapPayload, bytes snapSignature);
+    event InvalidStateWithSnapshot(uint8 stateIndex, bytes snapPayload, bytes snapSignature);
 
     /**
      * @notice Emitted when a proof of invalid state report is submitted.
diff --git a/packages/contracts-core/contracts/hubs/ExecutionHub.sol b/packages/contracts-core/contracts/hubs/ExecutionHub.sol
index 300452061c..fec576fcdb 100644
--- a/packages/contracts-core/contracts/hubs/ExecutionHub.sol
+++ b/packages/contracts-core/contracts/hubs/ExecutionHub.sol
@@ -27,6 +27,7 @@ import {Request} from "../libs/stack/Request.sol";
 import {SnapshotLib} from "../libs/memory/Snapshot.sol";
 import {AgentFlag, AgentStatus, MessageStatus} from "../libs/Structures.sol";
 import {Tips} from "../libs/stack/Tips.sol";
+import {ChainContext} from "../libs/ChainContext.sol";
 import {TypeCasts} from "../libs/TypeCasts.sol";
 // ═════════════════════════════ INTERNAL IMPORTS ══════════════════════════════
 import {AgentSecured} from "../base/AgentSecured.sol";
@@ -36,6 +37,7 @@ import {IExecutionHub} from "../interfaces/IExecutionHub.sol";
 import {IMessageRecipient} from "../interfaces/IMessageRecipient.sol";
 // ═════════════════════════════ EXTERNAL IMPORTS ══════════════════════════════
 import {Address} from "@openzeppelin/contracts/utils/Address.sol";
+import {SafeCast} from "@openzeppelin/contracts/utils/math/SafeCast.sol";
 import {ReentrancyGuardUpgradeable} from "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
 
 /// @notice `ExecutionHub` is a parent contract for `Destination`. It is responsible for the following:
@@ -52,6 +54,7 @@ abstract contract ExecutionHub is AgentSecured, ReentrancyGuardUpgradeable, Exec
     using MessageLib for bytes;
     using ReceiptLib for bytes;
     using SafeCall for address;
+    using SafeCast for uint256;
     using TypeCasts for bytes32;
 
     /// @notice Struct representing stored data for the snapshot root
@@ -115,7 +118,7 @@ abstract contract ExecutionHub is AgentSecured, ReentrancyGuardUpgradeable, Exec
         bytes memory msgPayload,
         bytes32[] calldata originProof,
         bytes32[] calldata snapProof,
-        uint256 stateIndex,
+        uint8 stateIndex,
         uint64 gasLimit
     ) external nonReentrant {
         // This will revert if payload is not a formatted message payload
@@ -150,7 +153,7 @@ abstract contract ExecutionHub is AgentSecured, ReentrancyGuardUpgradeable, Exec
             // This is the first valid attempt to execute the message => save origin and snapshot proof
             rcptData.origin = header.origin();
             rcptData.rootIndex = rootData.index;
-            rcptData.stateIndex = uint8(stateIndex);
+            rcptData.stateIndex = stateIndex;
             if (success) {
                 // This is the successful attempt to execute the message => save the executor
                 rcptData.executor = msg.sender;
@@ -284,13 +287,14 @@ abstract contract ExecutionHub is AgentSecured, ReentrancyGuardUpgradeable, Exec
     function _saveAttestation(Attestation att, uint32 notaryIndex, uint256 sigIndex) internal {
         bytes32 root = att.snapRoot();
         if (_rootData[root].submittedAt != 0) revert DuplicatedSnapshotRoot();
+        // TODO: consider using more than 32 bits for the root index
         _rootData[root] = SnapRootData({
             notaryIndex: notaryIndex,
             attNonce: att.nonce(),
             attBN: att.blockNumber(),
             attTS: att.timestamp(),
-            index: uint32(_roots.length),
-            submittedAt: uint40(block.timestamp),
+            index: _roots.length.toUint32(),
+            submittedAt: ChainContext.blockTimestamp(),
             sigIndex: sigIndex
         });
         _roots.push(root);
@@ -347,7 +351,7 @@ abstract contract ExecutionHub is AgentSecured, ReentrancyGuardUpgradeable, Exec
         bytes32 msgLeaf,
         bytes32[] calldata originProof,
         bytes32[] calldata snapProof,
-        uint256 stateIndex
+        uint8 stateIndex
     ) internal view returns (SnapRootData memory rootData) {
         // Reconstruct Origin Merkle Root using the origin proof
         // Message index in the tree is (nonce - 1), as nonce starts from 1
diff --git a/packages/contracts-core/contracts/hubs/SnapshotHub.sol b/packages/contracts-core/contracts/hubs/SnapshotHub.sol
index d3e6cdd0b7..70199d4994 100644
--- a/packages/contracts-core/contracts/hubs/SnapshotHub.sol
+++ b/packages/contracts-core/contracts/hubs/SnapshotHub.sol
@@ -10,6 +10,7 @@ import {ChainGas, GasData, GasDataLib} from "../libs/stack/GasData.sol";
 import {MerkleMath} from "../libs/merkle/MerkleMath.sol";
 import {Snapshot, SnapshotLib} from "../libs/memory/Snapshot.sol";
 import {State, StateLib} from "../libs/memory/State.sol";
+import {ChainContext} from "../libs/ChainContext.sol";
 // ═════════════════════════════ INTERNAL IMPORTS ══════════════════════════════
 import {AgentSecured} from "../base/AgentSecured.sol";
 import {SnapshotHubEvents} from "../events/SnapshotHubEvents.sol";
@@ -168,7 +169,7 @@ abstract contract SnapshotHub is AgentSecured, SnapshotHubEvents, ISnapshotHub {
     }
 
     /// @inheritdoc ISnapshotHub
-    function getSnapshotProof(uint32 attNonce, uint256 stateIndex) external view returns (bytes32[] memory snapProof) {
+    function getSnapshotProof(uint32 attNonce, uint8 stateIndex) external view returns (bytes32[] memory snapProof) {
         if (attNonce == 0 || attNonce >= _notarySnapshots.length) revert NonceOutOfRange();
         SummitSnapshot memory snap = _notarySnapshots[attNonce];
         uint256 statesAmount = snap.statePtrs.length;
@@ -299,11 +300,6 @@ abstract contract SnapshotHub is AgentSecured, SnapshotHubEvents, ISnapshotHub {
 
     // ══════════════════════════════════════════════ INTERNAL VIEWS ═══════════════════════════════════════════════════
 
-    /// @dev Returns the amount of saved _attestations (created from Notary snapshots) so far.
-    function _attestationsAmount() internal view returns (uint256) {
-        return _attestations.length;
-    }
-
     /// @dev Checks if attestation was previously submitted by a Notary (as a signed snapshot).
     function _isValidAttestation(Attestation att) internal view returns (bool) {
         // Check if nonce exists
@@ -353,7 +349,7 @@ abstract contract SnapshotHub is AgentSecured, SnapshotHubEvents, ISnapshotHub {
     }
 
     /// @dev Returns indexes of agents who provided state data for the Notary snapshot with the given nonce.
-    function _stateAgents(uint32 nonce, uint256 stateIndex)
+    function _stateAgents(uint32 nonce, uint8 stateIndex)
         internal
         view
         returns (uint32 guardIndex, uint32 notaryIndex)
@@ -431,8 +427,8 @@ abstract contract SnapshotHub is AgentSecured, SnapshotHubEvents, ISnapshotHub {
         summitAtt.snapRoot = snapRoot;
         summitAtt.agentRoot = agentRoot;
         summitAtt.snapGasHash = snapGasHash;
-        summitAtt.blockNumber = uint40(block.number);
-        summitAtt.timestamp = uint40(block.timestamp);
+        summitAtt.blockNumber = ChainContext.blockNumber();
+        summitAtt.timestamp = ChainContext.blockTimestamp();
     }
 
     /// @dev Checks that an Attestation and its Summit representation are equal.
diff --git a/packages/contracts-core/contracts/hubs/StateHub.sol b/packages/contracts-core/contracts/hubs/StateHub.sol
index 8a4d9c891b..b5ce9874ff 100644
--- a/packages/contracts-core/contracts/hubs/StateHub.sol
+++ b/packages/contracts-core/contracts/hubs/StateHub.sol
@@ -6,15 +6,19 @@ import {IncorrectOriginDomain} from "../libs/Errors.sol";
 import {GasData, GasDataLib} from "../libs/stack/GasData.sol";
 import {HistoricalTree} from "../libs/merkle/MerkleTree.sol";
 import {State, StateLib} from "../libs/memory/State.sol";
+import {ChainContext} from "../libs/ChainContext.sol";
 // ═════════════════════════════ INTERNAL IMPORTS ══════════════════════════════
 import {AgentSecured} from "../base/AgentSecured.sol";
 import {StateHubEvents} from "../events/StateHubEvents.sol";
 import {IStateHub} from "../interfaces/IStateHub.sol";
+// ═════════════════════════════ EXTERNAL IMPORTS ══════════════════════════════
+import {SafeCast} from "@openzeppelin/contracts/utils/math/SafeCast.sol";
 
 /// @notice `StateHub` is a parent contract for `Origin`. It is responsible for the following:
 /// - Keeping track of the historical Origin Merkle Tree containing all the message hashes.
 /// - Keeping track of the historical Origin States, as well as verifying their validity.
 abstract contract StateHub is AgentSecured, StateHubEvents, IStateHub {
+    using SafeCast for uint256;
     using StateLib for bytes;
 
     struct OriginState {
@@ -93,7 +97,8 @@ abstract contract StateHub is AgentSecured, StateHubEvents, IStateHub {
     /// @dev Returns nonce of the next sent message: the amount of saved States so far.
     /// This always equals to "total amount of sent messages" plus 1.
     function _nextNonce() internal view returns (uint32) {
-        return uint32(_originStates.length);
+        // TODO: consider using more than 32 bits for origin nonces
+        return _originStates.length.toUint32();
     }
 
     /// @dev Checks if a state is valid, i.e. if it matches the historical one.
@@ -135,8 +140,8 @@ abstract contract StateHub is AgentSecured, StateHubEvents, IStateHub {
 
     /// @dev Returns a OriginState struct to save in the contract.
     function _toOriginState() internal view returns (OriginState memory originState) {
-        originState.blockNumber = uint40(block.number);
-        originState.timestamp = uint40(block.timestamp);
+        originState.blockNumber = ChainContext.blockNumber();
+        originState.timestamp = ChainContext.blockTimestamp();
         originState.gasData = _fetchGasData();
     }
 
diff --git a/packages/contracts-core/contracts/inbox/StatementInbox.sol b/packages/contracts-core/contracts/inbox/StatementInbox.sol
index 776c64d567..4a95c940aa 100644
--- a/packages/contracts-core/contracts/inbox/StatementInbox.sol
+++ b/packages/contracts-core/contracts/inbox/StatementInbox.sol
@@ -79,7 +79,7 @@ abstract contract StatementInbox is MessagingBase, StatementInboxEvents, IStatem
     /// @inheritdoc IStatementInbox
     // solhint-disable-next-line ordering
     function submitStateReportWithSnapshot(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory srSignature,
         bytes memory snapPayload,
         bytes memory snapSignature
@@ -107,7 +107,7 @@ abstract contract StatementInbox is MessagingBase, StatementInboxEvents, IStatem
 
     /// @inheritdoc IStatementInbox
     function submitStateReportWithAttestation(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory srSignature,
         bytes memory snapPayload,
         bytes memory attPayload,
@@ -138,7 +138,7 @@ abstract contract StatementInbox is MessagingBase, StatementInboxEvents, IStatem
 
     /// @inheritdoc IStatementInbox
     function submitStateReportWithSnapshotProof(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory statePayload,
         bytes memory srSignature,
         bytes32[] memory snapProof,
@@ -212,7 +212,7 @@ abstract contract StatementInbox is MessagingBase, StatementInboxEvents, IStatem
 
     /// @inheritdoc IStatementInbox
     function verifyStateWithAttestation(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory snapPayload,
         bytes memory attPayload,
         bytes memory attSignature
@@ -237,7 +237,7 @@ abstract contract StatementInbox is MessagingBase, StatementInboxEvents, IStatem
 
     /// @inheritdoc IStatementInbox
     function verifyStateWithSnapshotProof(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory statePayload,
         bytes32[] memory snapProof,
         bytes memory attPayload,
@@ -266,7 +266,7 @@ abstract contract StatementInbox is MessagingBase, StatementInboxEvents, IStatem
     }
 
     /// @inheritdoc IStatementInbox
-    function verifyStateWithSnapshot(uint256 stateIndex, bytes memory snapPayload, bytes memory snapSignature)
+    function verifyStateWithSnapshot(uint8 stateIndex, bytes memory snapPayload, bytes memory snapSignature)
         external
         returns (bool isValidState)
     {
@@ -520,7 +520,7 @@ abstract contract StatementInbox is MessagingBase, StatementInboxEvents, IStatem
      * @param state             Typed memory view over the provided state payload
      * @param snapProof         Raw payload with snapshot data
      */
-    function _verifySnapshotMerkle(Attestation att, uint256 stateIndex, State state, bytes32[] memory snapProof)
+    function _verifySnapshotMerkle(Attestation att, uint8 stateIndex, State state, bytes32[] memory snapProof)
         internal
         pure
     {
diff --git a/packages/contracts-core/contracts/interfaces/IExecutionHub.sol b/packages/contracts-core/contracts/interfaces/IExecutionHub.sol
index 77b89a924c..fa4bb443cc 100644
--- a/packages/contracts-core/contracts/interfaces/IExecutionHub.sol
+++ b/packages/contracts-core/contracts/interfaces/IExecutionHub.sol
@@ -29,7 +29,7 @@ interface IExecutionHub {
         bytes memory msgPayload,
         bytes32[] calldata originProof,
         bytes32[] calldata snapProof,
-        uint256 stateIndex,
+        uint8 stateIndex,
         uint64 gasLimit
     ) external;
 
diff --git a/packages/contracts-core/contracts/interfaces/ISnapshotHub.sol b/packages/contracts-core/contracts/interfaces/ISnapshotHub.sol
index d28630e405..ff84385876 100644
--- a/packages/contracts-core/contracts/interfaces/ISnapshotHub.sol
+++ b/packages/contracts-core/contracts/interfaces/ISnapshotHub.sol
@@ -93,5 +93,5 @@ interface ISnapshotHub {
      * @param stateIndex    Index of state in the attestation's snapshot
      * @return snapProof    The snapshot proof
      */
-    function getSnapshotProof(uint32 attNonce, uint256 stateIndex) external view returns (bytes32[] memory snapProof);
+    function getSnapshotProof(uint32 attNonce, uint8 stateIndex) external view returns (bytes32[] memory snapProof);
 }
diff --git a/packages/contracts-core/contracts/interfaces/IStatementInbox.sol b/packages/contracts-core/contracts/interfaces/IStatementInbox.sol
index d223ac5cff..22c1471511 100644
--- a/packages/contracts-core/contracts/interfaces/IStatementInbox.sol
+++ b/packages/contracts-core/contracts/interfaces/IStatementInbox.sol
@@ -24,7 +24,7 @@ interface IStatementInbox {
      * @return wasAccepted      Whether the Report was accepted (resulting in Dispute between the agents)
      */
     function submitStateReportWithSnapshot(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory srSignature,
         bytes memory snapPayload,
         bytes memory snapSignature
@@ -53,7 +53,7 @@ interface IStatementInbox {
      * @return wasAccepted      Whether the Report was accepted (resulting in Dispute between the agents)
      */
     function submitStateReportWithAttestation(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory srSignature,
         bytes memory snapPayload,
         bytes memory attPayload,
@@ -86,7 +86,7 @@ interface IStatementInbox {
      * @return wasAccepted      Whether the Report was accepted (resulting in Dispute between the agents)
      */
     function submitStateReportWithSnapshotProof(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory statePayload,
         bytes memory srSignature,
         bytes32[] memory snapProof,
@@ -149,7 +149,7 @@ interface IStatementInbox {
      *                          Notary is slashed, if return value is FALSE.
      */
     function verifyStateWithAttestation(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory snapPayload,
         bytes memory attPayload,
         bytes memory attSignature
@@ -177,7 +177,7 @@ interface IStatementInbox {
      *                          Notary is slashed, if return value is FALSE.
      */
     function verifyStateWithSnapshotProof(
-        uint256 stateIndex,
+        uint8 stateIndex,
         bytes memory statePayload,
         bytes32[] memory snapProof,
         bytes memory attPayload,
@@ -199,7 +199,7 @@ interface IStatementInbox {
      * @return isValidState     Whether the provided state is valid.
      *                          Agent is slashed, if return value is FALSE.
      */
-    function verifyStateWithSnapshot(uint256 stateIndex, bytes memory snapPayload, bytes memory snapSignature)
+    function verifyStateWithSnapshot(uint8 stateIndex, bytes memory snapPayload, bytes memory snapSignature)
         external
         returns (bool isValidState);
 
diff --git a/packages/contracts-core/contracts/libs/ChainContext.sol b/packages/contracts-core/contracts/libs/ChainContext.sol
new file mode 100644
index 0000000000..290dce4120
--- /dev/null
+++ b/packages/contracts-core/contracts/libs/ChainContext.sol
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.17;
+
+import {SafeCast} from "@openzeppelin/contracts/utils/math/SafeCast.sol";
+
+/// @notice Library for accessing chain context variables as tightly packed integers.
+/// Messaging contracts should rely on this library for accessing chain context variables
+/// instead of doing the casting themselves.
+library ChainContext {
+    using SafeCast for uint256;
+
+    /// @notice Returns the current block number as uint40.
+    /// @dev Reverts if block number is greater than 40 bits, which is not supposed to happen
+    /// until the block.timestamp overflows (assuming block time is at least 1 second).
+    function blockNumber() internal view returns (uint40) {
+        return block.number.toUint40();
+    }
+
+    /// @notice Returns the current block timestamp as uint40.
+    /// @dev Reverts if block timestamp is greater than 40 bits, which is
+    /// supposed to happen approximately in year 36835.
+    function blockTimestamp() internal view returns (uint40) {
+        return block.timestamp.toUint40();
+    }
+
+    /// @notice Returns the chain id as uint32.
+    /// @dev Reverts if chain id is greater than 32 bits, which is not
+    /// supposed to happen in production.
+    function chainId() internal view returns (uint32) {
+        return block.chainid.toUint32();
+    }
+}
diff --git a/packages/contracts-core/contracts/libs/memory/Attestation.sol b/packages/contracts-core/contracts/libs/memory/Attestation.sol
index 89f5099aba..1f0f2ec596 100644
--- a/packages/contracts-core/contracts/libs/memory/Attestation.sol
+++ b/packages/contracts-core/contracts/libs/memory/Attestation.sol
@@ -147,17 +147,20 @@ library AttestationLib {
 
     /// @notice Returns nonce of Summit contract at the time, when attestation was created.
     function nonce(Attestation att) internal pure returns (uint32) {
+        // Can be safely casted to uint32, since we index 4 bytes
         return uint32(att.unwrap().indexUint({index_: OFFSET_NONCE, bytes_: 4}));
     }
 
     /// @notice Returns a block number when attestation was created in Summit.
     function blockNumber(Attestation att) internal pure returns (uint40) {
+        // Can be safely casted to uint40, since we index 5 bytes
         return uint40(att.unwrap().indexUint({index_: OFFSET_BLOCK_NUMBER, bytes_: 5}));
     }
 
     /// @notice Returns a block timestamp when attestation was created in Summit.
     /// @dev This is the timestamp according to the Synapse Chain.
     function timestamp(Attestation att) internal pure returns (uint40) {
+        // Can be safely casted to uint40, since we index 5 bytes
         return uint40(att.unwrap().indexUint({index_: OFFSET_TIMESTAMP, bytes_: 5}));
     }
 }
diff --git a/packages/contracts-core/contracts/libs/memory/ByteString.sol b/packages/contracts-core/contracts/libs/memory/ByteString.sol
index b3c8b84a8d..e8ca65d919 100644
--- a/packages/contracts-core/contracts/libs/memory/ByteString.sol
+++ b/packages/contracts-core/contracts/libs/memory/ByteString.sol
@@ -96,6 +96,7 @@ library ByteString {
         MemView memView = unwrap(signature);
         r = memView.index({index_: OFFSET_R, bytes_: 32});
         s = memView.index({index_: OFFSET_S, bytes_: 32});
+        // Can be safely casted to uint8, since we index a single byte
         v = uint8(memView.indexUint({index_: OFFSET_V, bytes_: 1}));
     }
 
diff --git a/packages/contracts-core/contracts/libs/memory/Receipt.sol b/packages/contracts-core/contracts/libs/memory/Receipt.sol
index fbc2471e8f..832503dc35 100644
--- a/packages/contracts-core/contracts/libs/memory/Receipt.sol
+++ b/packages/contracts-core/contracts/libs/memory/Receipt.sol
@@ -124,11 +124,13 @@ library ReceiptLib {
 
     /// @notice Returns receipt's origin field
     function origin(Receipt receipt) internal pure returns (uint32) {
+        // Can be safely casted to uint32, since we index 4 bytes
         return uint32(receipt.unwrap().indexUint({index_: OFFSET_ORIGIN, bytes_: 4}));
     }
 
     /// @notice Returns receipt's destination field
     function destination(Receipt receipt) internal pure returns (uint32) {
+        // Can be safely casted to uint32, since we index 4 bytes
         return uint32(receipt.unwrap().indexUint({index_: OFFSET_DESTINATION, bytes_: 4}));
     }
 
@@ -144,6 +146,7 @@ library ReceiptLib {
 
     /// @notice Returns receipt's "state index" field
     function stateIndex(Receipt receipt) internal pure returns (uint8) {
+        // Can be safely casted to uint8, since we index a single byte
         return uint8(receipt.unwrap().indexUint({index_: OFFSET_STATE_INDEX, bytes_: 1}));
     }
 
diff --git a/packages/contracts-core/contracts/libs/memory/Snapshot.sol b/packages/contracts-core/contracts/libs/memory/Snapshot.sol
index 5dc2905baf..3e34d18907 100644
--- a/packages/contracts-core/contracts/libs/memory/Snapshot.sol
+++ b/packages/contracts-core/contracts/libs/memory/Snapshot.sol
@@ -161,16 +161,18 @@ library SnapshotLib {
     /// @param domain        Domain of Origin chain
     /// @param snapProof     Proof of inclusion of State Merkle Data into Snapshot Merkle Tree
     /// @param stateIndex    Index of Origin State in the Snapshot
-    function proofSnapRoot(bytes32 originRoot, uint32 domain, bytes32[] memory snapProof, uint256 stateIndex)
+    function proofSnapRoot(bytes32 originRoot, uint32 domain, bytes32[] memory snapProof, uint8 stateIndex)
         internal
         pure
         returns (bytes32)
     {
         // Index of "leftLeaf" is twice the state position in the snapshot
-        uint256 leftLeafIndex = stateIndex << 1;
+        // This is because each state is represented by two leaves in the Snapshot Merkle Tree:
+        // - leftLeaf is a hash of (originRoot, originDomain)
+        // - rightLeaf is a hash of (nonce, blockNumber, timestamp, gasData)
+        uint256 leftLeafIndex = uint256(stateIndex) << 1;
         // Check that "leftLeaf" index fits into Snapshot Merkle Tree
         if (leftLeafIndex >= (1 << SNAPSHOT_TREE_HEIGHT)) revert IndexOutOfRange();
-        // Reconstruct left sub-leaf of the Origin State: (originRoot, originDomain)
         bytes32 leftLeaf = StateLib.leftLeaf(originRoot, domain);
         // Reconstruct snapshot root using proof of inclusion
         // This will revert if snapshot proof length exceeds Snapshot Tree Height
diff --git a/packages/contracts-core/contracts/libs/memory/State.sol b/packages/contracts-core/contracts/libs/memory/State.sol
index 78b53b9cb5..d3fcb113c2 100644
--- a/packages/contracts-core/contracts/libs/memory/State.sol
+++ b/packages/contracts-core/contracts/libs/memory/State.sol
@@ -156,22 +156,26 @@ library StateLib {
 
     /// @notice Returns domain of chain where the Origin contract is deployed.
     function origin(State state) internal pure returns (uint32) {
+        // Can be safely casted to uint32, since we index 4 bytes
         return uint32(state.unwrap().indexUint({index_: OFFSET_ORIGIN, bytes_: 4}));
     }
 
     /// @notice Returns nonce of Origin contract at the time, when `root` was the Merkle root.
     function nonce(State state) internal pure returns (uint32) {
+        // Can be safely casted to uint32, since we index 4 bytes
         return uint32(state.unwrap().indexUint({index_: OFFSET_NONCE, bytes_: 4}));
     }
 
     /// @notice Returns a block number when `root` was saved in Origin.
     function blockNumber(State state) internal pure returns (uint40) {
+        // Can be safely casted to uint40, since we index 5 bytes
         return uint40(state.unwrap().indexUint({index_: OFFSET_BLOCK_NUMBER, bytes_: 5}));
     }
 
     /// @notice Returns a block timestamp when `root` was saved in Origin.
     /// @dev This is the timestamp according to the origin chain.
     function timestamp(State state) internal pure returns (uint40) {
+        // Can be safely casted to uint40, since we index 5 bytes
         return uint40(state.unwrap().indexUint({index_: OFFSET_TIMESTAMP, bytes_: 5}));
     }
 
diff --git a/packages/contracts-core/contracts/libs/stack/GasData.sol b/packages/contracts-core/contracts/libs/stack/GasData.sol
index 3670dd22ae..d4845d96ad 100644
--- a/packages/contracts-core/contracts/libs/stack/GasData.sol
+++ b/packages/contracts-core/contracts/libs/stack/GasData.sol
@@ -74,6 +74,7 @@ library GasDataLib {
         Number etherPrice_,
         Number markup_
     ) internal pure returns (GasData) {
+        // Number type wraps uint16, so could safely be casted to uint96
         // forgefmt: disable-next-item
         return GasData.wrap(
             uint96(Number.unwrap(gasPrice_)) << SHIFT_GAS_PRICE |
@@ -87,6 +88,7 @@ library GasDataLib {
 
     /// @notice Wraps padded uint256 value into GasData struct.
     function wrapGasData(uint256 paddedGasData) internal pure returns (GasData) {
+        // Casting to uint96 will truncate the highest bits, which is the behavior we want
         return GasData.wrap(uint96(paddedGasData));
     }
 
@@ -132,11 +134,13 @@ library GasDataLib {
     /// @param gasData_ Chain's gas data
     /// @param domain_  Chain's domain
     function encodeChainGas(GasData gasData_, uint32 domain_) internal pure returns (ChainGas) {
+        // GasData type wraps uint96, so could safely be casted to uint128
         return ChainGas.wrap(uint128(GasData.unwrap(gasData_)) << SHIFT_GAS_DATA | uint128(domain_));
     }
 
     /// @notice Wraps padded uint256 value into ChainGas struct.
     function wrapChainGas(uint256 paddedChainGas) internal pure returns (ChainGas) {
+        // Casting to uint128 will truncate the highest bits, which is the behavior we want
         return ChainGas.wrap(uint128(paddedChainGas));
     }
 
diff --git a/packages/contracts-core/contracts/libs/stack/Header.sol b/packages/contracts-core/contracts/libs/stack/Header.sol
index 9989acf1de..079fe04666 100644
--- a/packages/contracts-core/contracts/libs/stack/Header.sol
+++ b/packages/contracts-core/contracts/libs/stack/Header.sol
@@ -53,6 +53,7 @@ library HeaderLib {
         uint32 destination_,
         uint32 optimisticPeriod_
     ) internal pure returns (Header) {
+        // All casts below are upcasts, so they are safe
         // forgefmt: disable-next-item
         return Header.wrap(
             uint136(uint8(flag_)) << SHIFT_FLAG |
@@ -77,6 +78,7 @@ library HeaderLib {
     function wrapPadded(uint256 paddedHeader) internal pure returns (Header) {
         // Check that flag is within range
         if (!isHeader(paddedHeader)) revert FlagOutOfRange();
+        // Casting to uint136 will truncate the highest bits, which is the behavior we want
         return Header.wrap(uint136(paddedHeader));
     }
 
diff --git a/packages/contracts-core/contracts/libs/stack/Number.sol b/packages/contracts-core/contracts/libs/stack/Number.sol
index 5ac3d5da59..556b032cbc 100644
--- a/packages/contracts-core/contracts/libs/stack/Number.sol
+++ b/packages/contracts-core/contracts/libs/stack/Number.sol
@@ -131,6 +131,7 @@ library NumberLib {
 
     /// @dev Wraps (mantissa, exponent) pair into Number.
     function _encode(uint8 mantissa, uint8 exponent) private pure returns (Number) {
+        // Casts below are upcasts, so they are safe.
         return Number.wrap(uint16(mantissa) << SHIFT_MANTISSA | uint16(exponent));
     }
 }
diff --git a/packages/contracts-core/contracts/libs/stack/Request.sol b/packages/contracts-core/contracts/libs/stack/Request.sol
index 7ccbf2010f..419b06d691 100644
--- a/packages/contracts-core/contracts/libs/stack/Request.sol
+++ b/packages/contracts-core/contracts/libs/stack/Request.sol
@@ -30,6 +30,7 @@ library RequestLib {
     /// @param gasLimit_    Minimum amount of gas units to supply for execution
     /// @param version_     Base message version to pass to the recipient
     function encodeRequest(uint96 gasDrop_, uint64 gasLimit_, uint32 version_) internal pure returns (Request) {
+        // Casts below are upcasts, so they are safe
         return Request.wrap(uint192(gasDrop_) << SHIFT_GAS_DROP | uint192(gasLimit_) << SHIFT_GAS_LIMIT | version_);
     }
 
@@ -39,6 +40,7 @@ library RequestLib {
     /// The highest bits are discarded, so that the contracts dealing with encoded requests
     /// don't need to be updated, if a new field is added.
     function wrapPadded(uint256 paddedRequest) internal pure returns (Request) {
+        // Casting to uint192 will truncate the highest bits, which is the behavior we want
         return Request.wrap(uint192(paddedRequest));
     }
 
diff --git a/packages/contracts-core/contracts/libs/stack/Tips.sol b/packages/contracts-core/contracts/libs/stack/Tips.sol
index d1a46b9212..465051480b 100644
--- a/packages/contracts-core/contracts/libs/stack/Tips.sol
+++ b/packages/contracts-core/contracts/libs/stack/Tips.sol
@@ -3,6 +3,7 @@ pragma solidity 0.8.17;
 
 import {TIPS_GRANULARITY} from "../Constants.sol";
 import {TipsOverflow, TipsValueTooLow} from "../Errors.sol";
+import {SafeCast} from "@openzeppelin/contracts/utils/math/SafeCast.sol";
 
 /// Tips is encoded data with "tips paid for sending a base message".
 /// Note: even though uint256 is also an underlying type for MemView, Tips is stored ON STACK.
@@ -48,6 +49,8 @@ using TipsLib for Tips global;
 /// | (008..000] | deliveryTip    | uint64 | 8     | Tip for successful message delivery on destination chain   |
 
 library TipsLib {
+    using SafeCast for uint256;
+
     /// @dev Amount of bits to shift to summitTip field
     uint256 private constant SHIFT_SUMMIT_TIP = 24 * 8;
     /// @dev Amount of bits to shift to attestationTip field
@@ -67,9 +70,12 @@ library TipsLib {
         pure
         returns (Tips)
     {
+        // forgefmt: disable-next-item
         return Tips.wrap(
-            uint256(summitTip_) << SHIFT_SUMMIT_TIP | uint256(attestationTip_) << SHIFT_ATTESTATION_TIP
-                | uint256(executionTip_) << SHIFT_EXECUTION_TIP | uint256(deliveryTip_)
+            uint256(summitTip_) << SHIFT_SUMMIT_TIP |
+            uint256(attestationTip_) << SHIFT_ATTESTATION_TIP |
+            uint256(executionTip_) << SHIFT_EXECUTION_TIP |
+            uint256(deliveryTip_)
         );
     }
 
@@ -79,11 +85,14 @@ library TipsLib {
         pure
         returns (Tips)
     {
+        // In practice, the tips amounts are not supposed to be higher than 2**96, and with 32 bits of granularity
+        // using uint64 is enough to store the values. However, we still check for overflow just in case.
+        // TODO: consider using Number type to store the tips values.
         return encodeTips({
-            summitTip_: uint64(summitTip_ >> TIPS_GRANULARITY),
-            attestationTip_: uint64(attestationTip_ >> TIPS_GRANULARITY),
-            executionTip_: uint64(executionTip_ >> TIPS_GRANULARITY),
-            deliveryTip_: uint64(deliveryTip_ >> TIPS_GRANULARITY)
+            summitTip_: (summitTip_ >> TIPS_GRANULARITY).toUint64(),
+            attestationTip_: (attestationTip_ >> TIPS_GRANULARITY).toUint64(),
+            executionTip_: (executionTip_ >> TIPS_GRANULARITY).toUint64(),
+            deliveryTip_: (deliveryTip_ >> TIPS_GRANULARITY).toUint64()
         });
     }
 
diff --git a/packages/contracts-core/contracts/manager/AgentManager.sol b/packages/contracts-core/contracts/manager/AgentManager.sol
index 8eadc20350..d027737170 100644
--- a/packages/contracts-core/contracts/manager/AgentManager.sol
+++ b/packages/contracts-core/contracts/manager/AgentManager.sol
@@ -98,9 +98,12 @@ abstract contract AgentManager is MessagingBase, AgentManagerEvents, IAgentManag
         if (_agentDispute[notaryIndex].flag != DisputeFlag.None) revert NotaryInDispute();
         _disputes.push(OpenedDispute(guardIndex, notaryIndex, 0));
         // Dispute is stored at length - 1, but we store the index + 1 to distinguish from "not in dispute".
-        uint256 disputePtr = _disputes.length;
-        _agentDispute[guardIndex] = AgentDispute(DisputeFlag.Pending, uint88(disputePtr), address(0));
-        _agentDispute[notaryIndex] = AgentDispute(DisputeFlag.Pending, uint88(disputePtr), address(0));
+        // TODO: check if we really need to use 88 bits for dispute indexes. Every dispute ends up in one of
+        // the agents being slashed, so the number of disputes is limited by the number of agents (currently 2**32).
+        // Thus we can do the unsafe cast to uint88.
+        uint88 disputePtr = uint88(_disputes.length);
+        _agentDispute[guardIndex] = AgentDispute(DisputeFlag.Pending, disputePtr, address(0));
+        _agentDispute[notaryIndex] = AgentDispute(DisputeFlag.Pending, disputePtr, address(0));
         // Dispute index is length - 1. Note: report that initiated the dispute has the same index in `Inbox`.
         emit DisputeOpened({disputeIndex: disputePtr - 1, guardIndex: guardIndex, notaryIndex: notaryIndex});
         _notifyDisputeOpened(guardIndex, notaryIndex);
diff --git a/packages/contracts-core/contracts/manager/BondingManager.sol b/packages/contracts-core/contracts/manager/BondingManager.sol
index 86cddeee2c..72805a8579 100644
--- a/packages/contracts-core/contracts/manager/BondingManager.sol
+++ b/packages/contracts-core/contracts/manager/BondingManager.sol
@@ -10,7 +10,6 @@ import {
     IncorrectAgentDomain,
     IncorrectOriginDomain,
     IndexOutOfRange,
-    MerkleTreeFull,
     MustBeSynapseDomain,
     SlashAgentOptimisticPeriod,
     SynapseDomainForbidden
@@ -24,6 +23,8 @@ import {IAgentSecured} from "../interfaces/IAgentSecured.sol";
 import {InterfaceBondingManager} from "../interfaces/InterfaceBondingManager.sol";
 import {InterfaceLightManager} from "../interfaces/InterfaceLightManager.sol";
 import {InterfaceOrigin} from "../interfaces/InterfaceOrigin.sol";
+// ═════════════════════════════ EXTERNAL IMPORTS ══════════════════════════════
+import {SafeCast} from "@openzeppelin/contracts/utils/math/SafeCast.sol";
 
 /// @notice BondingManager keeps track of all existing agents on the Synapse Chain.
 /// It utilizes a dynamic Merkle Tree to store the agent information. This enables passing only the
@@ -39,6 +40,8 @@ import {InterfaceOrigin} from "../interfaces/InterfaceOrigin.sol";
 /// - Accepting Manager Message from remote `LightManager` to slash agents on the Synapse Chain, when their fraud
 ///   is proven on the remote chain.
 contract BondingManager is AgentManager, InterfaceBondingManager {
+    using SafeCast for uint256;
+
     // ══════════════════════════════════════════════════ STORAGE ══════════════════════════════════════════════════════
 
     // The address of the Summit contract.
@@ -89,8 +92,8 @@ contract BondingManager is AgentManager, InterfaceBondingManager {
         if (status.flag == AgentFlag.Unknown) {
             // Unknown address could be added to any domain
             // New agent will need to be added to `_agents` list: could not have more than 2**32 agents
-            if (_agents.length >= type(uint32).max) revert MerkleTreeFull();
-            index = uint32(_agents.length);
+            // TODO: consider using more than 32 bits for agent indexes
+            index = _agents.length.toUint32();
             // Current leaf for index is bytes32(0), which is already assigned to `leaf`
             _agents.push(agent);
             _domainAgents[domain].push(agent);
diff --git a/packages/contracts-core/test/harnesses/client/ReentrantApp.t.sol b/packages/contracts-core/test/harnesses/client/ReentrantApp.t.sol
index d480cc66ce..6bbd790fd5 100644
--- a/packages/contracts-core/test/harnesses/client/ReentrantApp.t.sol
+++ b/packages/contracts-core/test/harnesses/client/ReentrantApp.t.sol
@@ -11,7 +11,7 @@ contract ReentrantApp is IMessageRecipient {
     bytes internal msgPayload;
     bytes32[] internal originProof;
     bytes32[] internal snapProof;
-    uint256 internal stateIndex;
+    uint8 internal stateIndex;
 
     /// @notice Prevents this contract from being included in the coverage report
     function testReentrantApp() external {}
@@ -20,7 +20,7 @@ contract ReentrantApp is IMessageRecipient {
         bytes memory msgPayload_,
         bytes32[] memory originProof_,
         bytes32[] memory snapProof_,
-        uint256 stateIndex_
+        uint8 stateIndex_
     ) external {
         msgPayload = msgPayload_;
         originProof = originProof_;
diff --git a/packages/contracts-core/test/harnesses/libs/ChainContextHarness.t.sol b/packages/contracts-core/test/harnesses/libs/ChainContextHarness.t.sol
new file mode 100644
index 0000000000..336b50b281
--- /dev/null
+++ b/packages/contracts-core/test/harnesses/libs/ChainContextHarness.t.sol
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.17;
+
+import {ChainContext} from "../../../contracts/libs/ChainContext.sol";
+
+contract ChainContextHarness {
+    function blockNumber() public view returns (uint40) {
+        return ChainContext.blockNumber();
+    }
+
+    function blockTimestamp() public view returns (uint40) {
+        return ChainContext.blockTimestamp();
+    }
+
+    function chainId() public view returns (uint32) {
+        return ChainContext.chainId();
+    }
+}
diff --git a/packages/contracts-core/test/harnesses/libs/memory/SnapshotHarness.t.sol b/packages/contracts-core/test/harnesses/libs/memory/SnapshotHarness.t.sol
index cdb90f7e94..8aae782459 100644
--- a/packages/contracts-core/test/harnesses/libs/memory/SnapshotHarness.t.sol
+++ b/packages/contracts-core/test/harnesses/libs/memory/SnapshotHarness.t.sol
@@ -39,7 +39,7 @@ contract SnapshotHarness {
         return payload.castToSnapshot().hashValid();
     }
 
-    function state(bytes memory payload, uint256 stateIndex) public view returns (bytes memory) {
+    function state(bytes memory payload, uint8 stateIndex) public view returns (bytes memory) {
         return payload.castToSnapshot().state(stateIndex).unwrap().clone();
     }
 
diff --git a/packages/contracts-core/test/mocks/hubs/ExecutionHubMock.t.sol b/packages/contracts-core/test/mocks/hubs/ExecutionHubMock.t.sol
index 77079aa3d5..d379d8104c 100644
--- a/packages/contracts-core/test/mocks/hubs/ExecutionHubMock.t.sol
+++ b/packages/contracts-core/test/mocks/hubs/ExecutionHubMock.t.sol
@@ -13,7 +13,7 @@ contract ExecutionHubMock is BaseMock, IExecutionHub {
         bytes memory msgPayload,
         bytes32[] calldata originProof,
         bytes32[] calldata snapProof,
-        uint256 stateIndex,
+        uint8 stateIndex,
         uint64 gasLimit
     ) external {}
 
diff --git a/packages/contracts-core/test/mocks/hubs/SnapshotHubMock.t.sol b/packages/contracts-core/test/mocks/hubs/SnapshotHubMock.t.sol
index 467072891a..78b69c4a14 100644
--- a/packages/contracts-core/test/mocks/hubs/SnapshotHubMock.t.sol
+++ b/packages/contracts-core/test/mocks/hubs/SnapshotHubMock.t.sol
@@ -45,5 +45,5 @@ contract SnapshotHubMock is BaseMock, ISnapshotHub {
         returns (bytes memory snapPayload, bytes memory snapSignature)
     {}
 
-    function getSnapshotProof(uint32 attNonce, uint256 stateIndex) external view returns (bytes32[] memory snapProof) {}
+    function getSnapshotProof(uint32 attNonce, uint8 stateIndex) external view returns (bytes32[] memory snapProof) {}
 }
diff --git a/packages/contracts-core/test/suite/Destination.t.sol b/packages/contracts-core/test/suite/Destination.t.sol
index e3bc89b722..cebaabf2f0 100644
--- a/packages/contracts-core/test/suite/Destination.t.sol
+++ b/packages/contracts-core/test/suite/Destination.t.sol
@@ -45,6 +45,12 @@ contract DestinationTest is ExecutionHubTest {
         assertFalse(rootPending);
     }
 
+    function test_constructor_revert_chainIdOverflow() public {
+        vm.chainId(2 ** 32);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        new Destination({synapseDomain_: 1, agentManager_: address(2), inbox_: address(3)});
+    }
+
     function test_cleanSetup(Random memory random) public override {
         uint32 domain = random.nextUint32();
         vm.assume(domain != DOMAIN_SYNAPSE);
@@ -166,6 +172,20 @@ contract DestinationTest is ExecutionHubTest {
         InterfaceDestination(localDestination()).acceptAttestation(0, 0, "", 0, new ChainGas[](0));
     }
 
+    function test_acceptAttestation_revert_blockTimestampOverflow() public {
+        address notary = domains[DOMAIN_LOCAL].agent;
+
+        Random memory random = Random("salt");
+        RawSnapshot memory rawSnap = random.nextSnapshot();
+        RawAttestation memory ra = random.nextAttestation({rawSnap: rawSnap, nonce: 1});
+        uint256[] memory snapGas = rawSnap.snapGas();
+        (bytes memory attPayload, bytes memory attSig) = signAttestation(notary, ra);
+
+        vm.warp(2 ** 40);
+        vm.expectRevert("SafeCast: value doesn't fit in 40 bits");
+        lightInbox.submitAttestation(attPayload, attSig, ra._agentRoot, snapGas);
+    }
+
     function test_acceptAttestation_revert_notaryInDispute(uint256 notaryId) public {
         address notary = domains[DOMAIN_LOCAL].agents[notaryId % DOMAIN_AGENTS];
         openDispute({guard: domains[0].agent, notary: notary});
diff --git a/packages/contracts-core/test/suite/GasOracle.MinimumTips.t.sol b/packages/contracts-core/test/suite/GasOracle.MinimumTips.t.sol
index 70c2c00310..5e33057e9e 100644
--- a/packages/contracts-core/test/suite/GasOracle.MinimumTips.t.sol
+++ b/packages/contracts-core/test/suite/GasOracle.MinimumTips.t.sol
@@ -8,7 +8,7 @@ import {Tips, TipsLib} from "../../contracts/libs/stack/Tips.sol";
 import {TIPS_MULTIPLIER} from "../../contracts/libs/Constants.sol";
 
 import {Random, GasOracle, GasOracleTest} from "./GasOracle.t.sol";
-import {RawGasData, RawGasData256} from "../utils/libs/SynapseStructs.t.sol";
+import {RawGasData, RawGasData256, RawRequest} from "../utils/libs/SynapseStructs.t.sol";
 
 // solhint-disable func-name-mixedcase
 // solhint-disable no-empty-blocks
@@ -75,7 +75,7 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
     function test_getMinimumTips_summitTip(Random memory random) public {
         uint256 summitTip = 1 << 48;
         testedGO().setSummitTip(summitTip);
-        uint256 paddedRequest = random.nextUint192();
+        uint256 paddedRequest = rawTestRequest(random).encodeRequest();
         uint256 contentLength = random.nextUint16();
         Tips tips = TipsLib.wrapPadded(testedGO().getMinimumTips(DOMAIN_REMOTE, paddedRequest, contentLength));
         // Local chain Ether price is 0.5 ETH, so the summit tip is worth 2x.
@@ -91,7 +91,7 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
     }
 
     function test_getMinimumTips_attestationTip(Random memory random) public {
-        uint256 paddedRequest = random.nextUint192();
+        uint256 paddedRequest = rawTestRequest(random).encodeRequest();
         uint256 contentLength = random.nextUint16();
         Tips tips = TipsLib.wrapPadded(testedGO().getMinimumTips(DOMAIN_REMOTE, paddedRequest, contentLength));
         // Remote chain Ether price is 2.0 ETH, local chain Ether price is 0.5 ETH.
@@ -110,12 +110,8 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
     }
 
     function test_getMinimumTips_executionTip(Random memory random) public {
-        Request request = RequestLib.encodeRequest({
-            gasDrop_: random.nextUint96(),
-            gasLimit_: random.nextUint32(),
-            version_: random.nextUint32()
-        });
-        uint256 paddedRequest = Request.unwrap(request);
+        RawRequest memory request = rawTestRequest(random);
+        uint256 paddedRequest = request.encodeRequest();
         uint256 contentLength = random.nextUint16();
         Tips tips = TipsLib.wrapPadded(testedGO().getMinimumTips(DOMAIN_REMOTE, paddedRequest, contentLength));
         // Remote chain Ether price is 2.0 ETH, local chain Ether price is 0.5 ETH.
@@ -123,7 +119,7 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
         // Execution tip is execBuffer + gasPrice * gasLimit + dataPrice * contentLength.
         assertEq(
             tips.executionTip() * TIPS_MULTIPLIER,
-            4 * (EXEC_BUFFER + GAS_PRICE * request.gasLimit() + DATA_PRICE * contentLength),
+            4 * (EXEC_BUFFER + GAS_PRICE * request.gasLimit + DATA_PRICE * contentLength),
             "!executionTip: 0.5ETH"
         );
         // Remote chain Ether price is 2.0 ETH, local chain Ether price is 2.0 ETH.
@@ -132,7 +128,7 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
         tips = TipsLib.wrapPadded(testedGO().getMinimumTips(DOMAIN_REMOTE, paddedRequest, contentLength));
         assertEq(
             tips.executionTip() * TIPS_MULTIPLIER,
-            EXEC_BUFFER + GAS_PRICE * request.gasLimit() + DATA_PRICE * contentLength,
+            EXEC_BUFFER + GAS_PRICE * request.gasLimit + DATA_PRICE * contentLength,
             "!executionTip: 2.0ETH"
         );
         // Remote chain Ether price is 2.0 ETH, local chain Ether price is 4.0 ETH.
@@ -141,18 +137,14 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
         tips = TipsLib.wrapPadded(testedGO().getMinimumTips(DOMAIN_REMOTE, paddedRequest, contentLength));
         assertEq(
             tips.executionTip() * TIPS_MULTIPLIER,
-            (EXEC_BUFFER + GAS_PRICE * request.gasLimit() + DATA_PRICE * contentLength) / 2,
+            (EXEC_BUFFER + GAS_PRICE * request.gasLimit + DATA_PRICE * contentLength) / 2,
             "!executionTip: 4.0ETH"
         );
     }
 
     function test_getMinimumTips_deliveryTip(Random memory random) public {
-        Request request = RequestLib.encodeRequest({
-            gasDrop_: random.nextUint96(),
-            gasLimit_: random.nextUint32(),
-            version_: random.nextUint32()
-        });
-        uint256 paddedRequest = Request.unwrap(request);
+        RawRequest memory request = rawTestRequest(random);
+        uint256 paddedRequest = request.encodeRequest();
         uint256 contentLength = random.nextUint16();
         Tips tips = TipsLib.wrapPadded(testedGO().getMinimumTips(DOMAIN_REMOTE, paddedRequest, contentLength));
         // Remote chain Ether price is 2.0 ETH, local chain Ether price is 0.5 ETH.
@@ -161,7 +153,7 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
         // Delivery tip is execution tip * markup (50%), therefore the final value is worth 2x.
         assertEq(
             tips.deliveryTip() * TIPS_MULTIPLIER,
-            2 * (EXEC_BUFFER + GAS_PRICE * request.gasLimit() + DATA_PRICE * contentLength),
+            2 * (EXEC_BUFFER + GAS_PRICE * request.gasLimit + DATA_PRICE * contentLength),
             "!deliveryTip: 0.5ETH"
         );
         // Remote chain Ether price is 2.0 ETH, local chain Ether price is 2.0 ETH.
@@ -171,7 +163,7 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
         tips = TipsLib.wrapPadded(testedGO().getMinimumTips(DOMAIN_REMOTE, paddedRequest, contentLength));
         assertEq(
             tips.deliveryTip() * TIPS_MULTIPLIER,
-            (EXEC_BUFFER + GAS_PRICE * request.gasLimit() + DATA_PRICE * contentLength) / 2,
+            (EXEC_BUFFER + GAS_PRICE * request.gasLimit + DATA_PRICE * contentLength) / 2,
             "!deliveryTip: 2.0ETH"
         );
         // Remote chain Ether price is 2.0 ETH, local chain Ether price is 4.0 ETH.
@@ -181,12 +173,18 @@ contract GasOracleMinimumTipsTest is GasOracleTest {
         tips = TipsLib.wrapPadded(testedGO().getMinimumTips(DOMAIN_REMOTE, paddedRequest, contentLength));
         assertEq(
             tips.deliveryTip() * TIPS_MULTIPLIER,
-            (EXEC_BUFFER + GAS_PRICE * request.gasLimit() + DATA_PRICE * contentLength) / 4,
+            (EXEC_BUFFER + GAS_PRICE * request.gasLimit + DATA_PRICE * contentLength) / 4,
             "!deliveryTip: 4.0ETH"
         );
         // TODO: adjust test when delivery tip will also include the value of gas airdrop.
     }
 
+    function rawTestRequest(Random memory random) internal pure returns (RawRequest memory rr) {
+        rr = random.nextRequest();
+        // Set sensible max values for gasDrop and gasLimit.
+        rr.boundRequest({maxGasDrop: 10 ** 20, maxGasLimit: 10 ** 8});
+    }
+
     function setLocalEtherPrice(uint256 etherPrice) public {
         testedGO().setGasData({
             domain: DOMAIN_LOCAL,
diff --git a/packages/contracts-core/test/suite/GasOracle.t.sol b/packages/contracts-core/test/suite/GasOracle.t.sol
index 24929df534..c5ad1ccfab 100644
--- a/packages/contracts-core/test/suite/GasOracle.t.sol
+++ b/packages/contracts-core/test/suite/GasOracle.t.sol
@@ -26,6 +26,12 @@ contract GasOracleTest is MessagingBaseTest {
         assertEq(cleanContract.destination(), destination_, "!destination");
     }
 
+    function test_constructor_revert_chainIdOverflow() public {
+        vm.chainId(2 ** 32);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        new GasOracle({synapseDomain_: 1, destination_: address(2)});
+    }
+
     function initializeLocalContract() public override {
         testedGO().initialize();
     }
diff --git a/packages/contracts-core/test/suite/Origin.t.sol b/packages/contracts-core/test/suite/Origin.t.sol
index 2c18c71265..0ff8797feb 100644
--- a/packages/contracts-core/test/suite/Origin.t.sol
+++ b/packages/contracts-core/test/suite/Origin.t.sol
@@ -63,6 +63,12 @@ contract OriginTest is AgentSecuredTest {
         assertEq(Versioned(origin).version(), LATEST_VERSION, "!version");
     }
 
+    function test_constructor_revert_chainIdOverflow() public {
+        vm.chainId(2 ** 32);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        new Origin({synapseDomain_: 1, agentManager_: address(2), inbox_: address(3), gasOracle_: address(4)});
+    }
+
     function test_cleanSetup(Random memory random) public override {
         uint32 domain = uint32(block.chainid);
         address caller = random.nextAddress();
@@ -85,6 +91,24 @@ contract OriginTest is AgentSecuredTest {
         Origin(localContract()).initialize();
     }
 
+    function test_sendBaseMessage_revert_blockTimestampOverflow() public {
+        vm.warp(2 ** 40);
+        vm.prank(sender);
+        vm.expectRevert("SafeCast: value doesn't fit in 40 bits");
+        InterfaceOrigin(origin).sendBaseMessage(
+            DOMAIN_REMOTE, addressToBytes32(recipient), period, request.encodeRequest(), "test content"
+        );
+    }
+
+    function test_sendBaseMessage_revert_blockNumberOverflow() public {
+        vm.roll(2 ** 40);
+        vm.prank(sender);
+        vm.expectRevert("SafeCast: value doesn't fit in 40 bits");
+        InterfaceOrigin(origin).sendBaseMessage(
+            DOMAIN_REMOTE, addressToBytes32(recipient), period, request.encodeRequest(), "test content"
+        );
+    }
+
     function test_sendBaseMessage_revert_tipsTooLow(RawTips memory minTips, uint256 msgValue) public {
         minTips.boundTips(1 ** 32);
         minTips.floorTips(1);
diff --git a/packages/contracts-core/test/suite/Summit.t.sol b/packages/contracts-core/test/suite/Summit.t.sol
index 2f4e297e29..fe5270a23d 100644
--- a/packages/contracts-core/test/suite/Summit.t.sol
+++ b/packages/contracts-core/test/suite/Summit.t.sol
@@ -68,6 +68,12 @@ contract SummitTest is AgentSecuredTest {
         assertEq(snapGas.length, 0, "!snapGas");
     }
 
+    function test_constructor_revert_chainIdOverflow() public {
+        vm.chainId(2 ** 32);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        new Summit({synapseDomain_: 1, agentManager_: address(2), inbox_: address(3)});
+    }
+
     function test_cleanSetup(Random memory random) public override {
         uint32 domain = DOMAIN_SYNAPSE;
         vm.chainId(domain);
@@ -101,6 +107,20 @@ contract SummitTest is AgentSecuredTest {
         InterfaceSummit(summit).acceptNotarySnapshot(0, 0, 0, "");
     }
 
+    function test_acceptNotarySnapshot_revert_blockTimestampOverflow() public {
+        address notary = domains[DOMAIN_LOCAL].agent;
+        address guard = domains[0].agent;
+        Random memory random = Random("salt");
+        RawSnapshot memory rawSnap = random.nextSnapshot();
+        // Another Guard signs the snapshot
+        (bytes memory snapPayload, bytes memory guardSignature) = signSnapshot(guard, rawSnap);
+        bytes memory notarySig = signSnapshot(notary, snapPayload);
+        inbox.submitSnapshot(snapPayload, guardSignature);
+        vm.warp(2 ** 40);
+        vm.expectRevert("SafeCast: value doesn't fit in 40 bits");
+        inbox.submitSnapshot(snapPayload, notarySig);
+    }
+
     function test_verifyAttestation_existingNonce(Random memory random, uint256 mask) public {
         test_notarySnapshots(random);
         // Restrict nonce to existing ones
@@ -290,7 +310,7 @@ contract SummitTest is AgentSecuredTest {
             assertEq(keccak256(abi.encodePacked(snapGas)), ra._snapGasHash, "!latestAttestation: gas hash");
 
             // Check proofs for every State in the Notary snapshot
-            for (uint256 j = 0; j < STATES; ++j) {
+            for (uint8 j = 0; j < STATES; ++j) {
                 bytes32[] memory snapProof = ISnapshotHub(summit).getSnapshotProof(ra.nonce, j);
                 // Item to prove is State's "left sub-leaf"
                 (bytes32 item,) = rs.states[j].castToState().subLeafs();
diff --git a/packages/contracts-core/test/suite/hubs/ExecutionHub.t.sol b/packages/contracts-core/test/suite/hubs/ExecutionHub.t.sol
index 30bf672862..c2152040aa 100644
--- a/packages/contracts-core/test/suite/hubs/ExecutionHub.t.sol
+++ b/packages/contracts-core/test/suite/hubs/ExecutionHub.t.sol
@@ -522,7 +522,7 @@ abstract contract ExecutionHubTest is AgentSecuredTest {
     function verify_messageStatus(
         bytes32 messageHash,
         bytes32 snapRoot,
-        uint256 stateIndex,
+        uint8 stateIndex,
         MessageStatus flag,
         address firstExecutor,
         address finalExecutor
@@ -625,7 +625,7 @@ abstract contract ExecutionHubTest is AgentSecuredTest {
         rbm.tips = RawTips(1, 1, 1, 1);
         rh.nonce = 1;
         rh.optimisticPeriod = random.nextUint32();
-        sm = SnapshotMock(random.nextState(), RawStateIndex(random.nextUint256(), random.nextUint256()));
+        sm = SnapshotMock(random.nextState(), RawStateIndex(random.nextUint8(), random.nextUint256()));
         sm.rsi.boundStateIndex();
     }
 
diff --git a/packages/contracts-core/test/suite/inbox/Inbox.t.sol b/packages/contracts-core/test/suite/inbox/Inbox.t.sol
index fd4a9ee25d..ba10073daf 100644
--- a/packages/contracts-core/test/suite/inbox/Inbox.t.sol
+++ b/packages/contracts-core/test/suite/inbox/Inbox.t.sol
@@ -67,6 +67,12 @@ contract InboxTest is StatementInboxTest {
         new Inbox(DOMAIN_SYNAPSE);
     }
 
+    function test_constructor_revert_chainIdOverflow() public {
+        vm.chainId(2 ** 32);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        new Inbox({synapseDomain_: DOMAIN_SYNAPSE});
+    }
+
     function initializeLocalContract() public override {
         Inbox(localContract()).initialize(address(0), address(0), address(0), address(0));
     }
diff --git a/packages/contracts-core/test/suite/inbox/LightInbox.t.sol b/packages/contracts-core/test/suite/inbox/LightInbox.t.sol
index 1ce66c4b88..8d0eb63d87 100644
--- a/packages/contracts-core/test/suite/inbox/LightInbox.t.sol
+++ b/packages/contracts-core/test/suite/inbox/LightInbox.t.sol
@@ -54,7 +54,13 @@ contract LightInboxTest is StatementInboxTest {
     function test_constructor_revert_onSynapseChain() public {
         vm.chainId(DOMAIN_SYNAPSE);
         vm.expectRevert(SynapseDomainForbidden.selector);
-        LightInbox inbox = new LightInbox(DOMAIN_SYNAPSE);
+        new LightInbox({synapseDomain_: DOMAIN_SYNAPSE});
+    }
+
+    function test_constructor_revert_chainIdOverflow() public {
+        vm.chainId(2 ** 32);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        new LightInbox({synapseDomain_: 1});
     }
 
     function initializeLocalContract() public override {
diff --git a/packages/contracts-core/test/suite/libs/ChainContext.t.sol b/packages/contracts-core/test/suite/libs/ChainContext.t.sol
new file mode 100644
index 0000000000..4ab1f4d1f6
--- /dev/null
+++ b/packages/contracts-core/test/suite/libs/ChainContext.t.sol
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.17;
+
+import {ChainContextHarness} from "../../harnesses/libs/ChainContextHarness.t.sol";
+
+import {SynapseLibraryTest} from "../../utils/SynapseLibraryTest.t.sol";
+
+// solhint-disable func-name-mixedcase
+contract ChainContextLibraryTest is SynapseLibraryTest {
+    ChainContextHarness public libHarness;
+
+    function setUp() public {
+        libHarness = new ChainContextHarness();
+    }
+
+    function test_blockNumber() public {
+        uint256 expectedBN = 1337;
+        vm.roll(expectedBN);
+        assertEq(libHarness.blockNumber(), expectedBN);
+    }
+
+    function test_blockNumber_maxValue() public {
+        uint256 expectedBN = 2 ** 40 - 1;
+        vm.roll(expectedBN);
+        assertEq(libHarness.blockNumber(), expectedBN);
+    }
+
+    function test_blockNumber_revert_blockNumberOverflow() public {
+        uint256 overflowBN = 2 ** 40;
+        vm.roll(overflowBN);
+        vm.expectRevert("SafeCast: value doesn't fit in 40 bits");
+        libHarness.blockNumber();
+    }
+
+    function test_blockTimestamp() public {
+        uint256 expectedBT = 7331;
+        vm.warp(expectedBT);
+        assertEq(libHarness.blockTimestamp(), expectedBT);
+    }
+
+    function test_blockTimestamp_maxValue() public {
+        uint256 expectedBT = 2 ** 40 - 1;
+        vm.warp(expectedBT);
+        assertEq(libHarness.blockTimestamp(), expectedBT);
+    }
+
+    function test_blockTimestamp_revert_blockTimestampOverflow() public {
+        uint256 overflowBT = 2 ** 40;
+        vm.warp(overflowBT);
+        vm.expectRevert("SafeCast: value doesn't fit in 40 bits");
+        libHarness.blockTimestamp();
+    }
+
+    function test_chainId() public {
+        uint256 expectedChainId = 420;
+        vm.chainId(expectedChainId);
+        assertEq(libHarness.chainId(), expectedChainId);
+    }
+
+    function test_chainId_maxValue() public {
+        uint256 expectedChainId = 2 ** 32 - 1;
+        vm.chainId(expectedChainId);
+        assertEq(libHarness.chainId(), expectedChainId);
+    }
+
+    function test_chainId_revert_chainIdOverflow() public {
+        uint256 overflowChainId = 2 ** 32;
+        vm.chainId(overflowChainId);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        libHarness.chainId();
+    }
+}
diff --git a/packages/contracts-core/test/suite/libs/memory/Snapshot.t.sol b/packages/contracts-core/test/suite/libs/memory/Snapshot.t.sol
index 55f8bf4d13..83648e6c1e 100644
--- a/packages/contracts-core/test/suite/libs/memory/Snapshot.t.sol
+++ b/packages/contracts-core/test/suite/libs/memory/Snapshot.t.sol
@@ -48,7 +48,7 @@ contract SnapshotLibraryTest is SynapseLibraryTest {
         // Test getters
         assertEq(libHarness.statesAmount(payload), statesAmount, "!statesAmount");
         ChainGas[] memory snapGas = libHarness.snapGas(payload);
-        for (uint256 i = 0; i < statesAmount; ++i) {
+        for (uint8 i = 0; i < statesAmount; ++i) {
             assertEq(libHarness.state(payload, i), statePayloads[i], "!state");
             assertEq(snapGas[i].domain(), states[i].origin, "!snapGas.domain");
             assertEq(GasData.unwrap(snapGas[i].gasData()), states[i].gasData.encodeGasData(), "!snapGas.gasData");
diff --git a/packages/contracts-core/test/suite/manager/BondingManager.t.sol b/packages/contracts-core/test/suite/manager/BondingManager.t.sol
index 4340ae0ee7..ec79e84fe8 100644
--- a/packages/contracts-core/test/suite/manager/BondingManager.t.sol
+++ b/packages/contracts-core/test/suite/manager/BondingManager.t.sol
@@ -60,6 +60,12 @@ contract BondingManagerTest is AgentManagerTest {
         new BondingManager(DOMAIN_SYNAPSE);
     }
 
+    function test_constructor_revert_chainIdOverflow() public {
+        vm.chainId(2 ** 32);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        new BondingManager(DOMAIN_SYNAPSE);
+    }
+
     function test_setup() public override {
         super.test_setup();
         assertEq(bondingManager.summit(), localSummit(), "!summit");
diff --git a/packages/contracts-core/test/suite/manager/LightManager.t.sol b/packages/contracts-core/test/suite/manager/LightManager.t.sol
index 0a90b8cc36..f43f523b52 100644
--- a/packages/contracts-core/test/suite/manager/LightManager.t.sol
+++ b/packages/contracts-core/test/suite/manager/LightManager.t.sol
@@ -45,6 +45,12 @@ contract LightManagerTest is AgentManagerTest {
         LightManager(localContract()).initialize(address(0), address(0), address(0));
     }
 
+    function test_constructor_revert_chainIdOverflow() public {
+        vm.chainId(2 ** 32);
+        vm.expectRevert("SafeCast: value doesn't fit in 32 bits");
+        new LightManager({synapseDomain_: 1});
+    }
+
     // ═══════════════════════════════════════════════ TESTS: SETUP ════════════════════════════════════════════════════
 
     function test_constructor_revert_onSynapseChain() public {
diff --git a/packages/contracts-core/test/utils/libs/FakeIt.t.sol b/packages/contracts-core/test/utils/libs/FakeIt.t.sol
index 0ea210e0ad..b44ae11fa0 100644
--- a/packages/contracts-core/test/utils/libs/FakeIt.t.sol
+++ b/packages/contracts-core/test/utils/libs/FakeIt.t.sol
@@ -36,5 +36,5 @@ function fakeSnapshot(RawState memory state, RawStateIndex memory rsi) pure retu
 /// @notice Returns RawSnapshot struct with fake states.
 function fakeSnapshot(uint256 statesAmount) pure returns (RawSnapshot memory rawSnap) {
     RawState memory state;
-    return fakeSnapshot(state, RawStateIndex(statesAmount, statesAmount));
+    return fakeSnapshot(state, RawStateIndex(uint8(statesAmount), statesAmount));
 }
diff --git a/packages/contracts-core/test/utils/libs/Random.t.sol b/packages/contracts-core/test/utils/libs/Random.t.sol
index 13bff11a96..df7436f4bd 100644
--- a/packages/contracts-core/test/utils/libs/Random.t.sol
+++ b/packages/contracts-core/test/utils/libs/Random.t.sol
@@ -7,6 +7,7 @@ import {
     RawExecReceipt,
     RawGasData,
     RawGasData256,
+    RawRequest,
     RawState,
     RawStateIndex,
     RawSnapshot
@@ -149,8 +150,14 @@ library RandomLib {
         return r.nextGasData256().compress();
     }
 
+    function nextRequest(Random memory r) internal pure returns (RawRequest memory rr) {
+        rr.gasDrop = r.nextUint96();
+        rr.gasLimit = r.nextUint64();
+        rr.version = r.nextUint32();
+    }
+
     function nextStateIndex(Random memory r) internal pure returns (RawStateIndex memory rsi) {
-        rsi.stateIndex = r.nextUint256();
+        rsi.stateIndex = r.nextUint8();
         rsi.statesAmount = r.nextUint256();
         rsi.boundStateIndex();
     }
diff --git a/packages/contracts-core/test/utils/libs/SynapseStructs.t.sol b/packages/contracts-core/test/utils/libs/SynapseStructs.t.sol
index af2fc75270..f8c791f3ea 100644
--- a/packages/contracts-core/test/utils/libs/SynapseStructs.t.sol
+++ b/packages/contracts-core/test/utils/libs/SynapseStructs.t.sol
@@ -150,7 +150,7 @@ struct RawState {
 using CastLib for RawState global;
 
 struct RawStateIndex {
-    uint256 stateIndex;
+    uint8 stateIndex;
     uint256 statesAmount;
 }
 
@@ -227,11 +227,19 @@ library CastLib {
         request = RequestLib.encodeRequest({gasDrop_: rr.gasDrop, gasLimit_: rr.gasLimit, version_: rr.version});
     }
 
+    function boundRequest(RawRequest memory rr, uint96 maxGasDrop, uint64 maxGasLimit) internal pure {
+        require(maxGasDrop != 0, "maxGasDrop can't be 0");
+        require(maxGasLimit != 0, "maxGasLimit can't be 0");
+        rr.gasDrop = rr.gasDrop % maxGasDrop;
+        rr.gasLimit = rr.gasLimit % maxGasLimit;
+    }
+
     function encodeTips(RawTips memory rt) internal pure returns (uint256 encodedTips) {
         encodedTips = Tips.unwrap(rt.castToTips());
     }
 
     function boundTips(RawTips memory rt, uint64 maxTipValue) internal pure {
+        require(maxTipValue != 0, "maxTipValue can't be 0");
         rt.summitTip = rt.summitTip % maxTipValue;
         rt.attestationTip = rt.attestationTip % maxTipValue;
         rt.executionTip = rt.executionTip % maxTipValue;
@@ -436,7 +444,7 @@ library CastLib {
         // [1 .. SNAPSHOT_MAX_STATES] range
         rsi.statesAmount = 1 + rsi.statesAmount % SNAPSHOT_MAX_STATES;
         // [0 .. statesAmount) range
-        rsi.stateIndex = rsi.stateIndex % rsi.statesAmount;
+        rsi.stateIndex = uint8(rsi.stateIndex % rsi.statesAmount);
     }
 
     // ═════════════════════════════════════════════════ SNAPSHOT ══════════════════════════════════════════════════════