diff --git a/packages/contracts/contracts/registry/AbstractGuardRegistry.sol b/packages/contracts/contracts/registry/AbstractGuardRegistry.sol
index 814121489a..a3937d5458 100644
--- a/packages/contracts/contracts/registry/AbstractGuardRegistry.sol
+++ b/packages/contracts/contracts/registry/AbstractGuardRegistry.sol
@@ -10,6 +10,15 @@ abstract contract AbstractGuardRegistry {
     using Report for bytes29;
     using TypedMemView for bytes29;
 
+    /**
+     * @notice  Checks all following statements are true:
+     *          - `_report` is a formatted Report payload
+     *          - `_report` contains a signature
+     *          - such signature belongs to an authorized Guard
+     * @param _report   Report on a Attestation of Origin merkle root
+     * @return _guard   Notary that signed the Attestation
+     * @return _view    Memory view on report
+     */
     function _checkGuardAuth(bytes memory _report)
         internal
         view
@@ -21,5 +30,11 @@ abstract contract AbstractGuardRegistry {
         require(_isGuard(_guard), "Signer is not a guard");
     }
 
-    function _isGuard(address _guard) internal view virtual returns (bool);
+    /**
+     * @notice Checks whether a given account in an authorized Guard.
+     * @dev Child contracts should implement this depending on how Guards are stored.
+     * @param _account  Address to check for being a Guard
+     * @return TRUE if the account is an authorized Guard.
+     */
+    function _isGuard(address _account) internal view virtual returns (bool);
 }