diff --git a/src/verifier/UserOpECDSAVerifier.sol b/src/verifier/UserOpECDSAVerifier.sol
index d97bc3d..94412b3 100644
--- a/src/verifier/UserOpECDSAVerifier.sol
+++ b/src/verifier/UserOpECDSAVerifier.sol
@@ -11,6 +11,17 @@ import {OnlyKeystore} from "../lib/OnlyKeystore.sol";
 contract UserOpECDSAVerifier is IVerifier, OnlyKeystore {
     constructor(address aKeystore) OnlyKeystore(aKeystore) {}
 
+    /**
+     * @notice Called by the Keystore for nodes with ECDSA verification.
+     * @param message The hashed message that was signed.
+     * @param data The raw signature or a PackedUserOperation containing the signature.
+     * If the length is more than 65 bytes, it will be decoded as a PackedUserOperation
+     * with the userop.signature field containing the packed (r,s,v) signature values.
+     * @param config The node configuration, expected to contain the 20 bytes ECDSA
+     * signer address.
+     * @return validationData Returns SIG_VALIDATION_SUCCESS (0) if ok, otherwise
+     * SIG_VALIDATION_FAILED (1).
+     */
     function validateData(bytes32 message, bytes calldata data, bytes calldata config)
         external
         view
diff --git a/src/verifier/UserOpMultiSigVerifier.sol b/src/verifier/UserOpMultiSigVerifier.sol
index 5bd4524..fe60e3a 100644
--- a/src/verifier/UserOpMultiSigVerifier.sol
+++ b/src/verifier/UserOpMultiSigVerifier.sol
@@ -18,6 +18,21 @@ contract UserOpMultiSigVerifier is IVerifier, OnlyKeystore {
 
     constructor(address aKeystore) OnlyKeystore(aKeystore) {}
 
+    /**
+     * @notice Called by the Keystore for nodes with multisig ECDSA verification.
+     * @param message The hashed message that must be signed by the owners.
+     * @param data The calldata containing the signatures. If the first byte is
+     * SIGNATURES_ONLY_TAG (0xff), it is followed by an abi-encoded array of SignerData
+     * structs. Otherwise, it is a PackedUserOperation whose signature field contains
+     * the abi-encoded array of SignerData.
+     * @param config The node configuration, expected to be abi.encoded as
+     * (uint8 threshold, address[] owners).
+     * The threshold is the minimum number of owner signatures required to pass
+     * validation.
+     * The owners array is all the valid signers on the multisig.
+     * @return validationData Returns SIG_VALIDATION_SUCCESS (0) if ok, otherwise
+     * SIG_VALIDATION_FAILED (1).
+     */
     function validateData(bytes32 message, bytes calldata data, bytes calldata config)
         external
         view
diff --git a/src/verifier/UserOpWebAuthnCosignVerifier.sol b/src/verifier/UserOpWebAuthnCosignVerifier.sol
index b27a84f..9f4c5bb 100644
--- a/src/verifier/UserOpWebAuthnCosignVerifier.sol
+++ b/src/verifier/UserOpWebAuthnCosignVerifier.sol
@@ -21,6 +21,24 @@ contract UserOpWebAuthnCosignVerifier is IVerifier, OnlyKeystore {
 
     constructor(address aKeystore) OnlyKeystore(aKeystore) {}
 
+    /**
+     * @notice Called by the Keystore for nodes with dual WebAuthn and ECDSA
+     * verification.
+     * @param message The hashed message that must be signed by both the ECDSA
+     * cosigner and the WebAuthn authenticator.
+     * @param data The calldata containing the ECDSA signature and the WebAuthn
+     * data. If the first byte is SIGNATURES_ONLY_TAG (0xff), it is followed by
+     * an abi-encoded (bytes ecdsaSignature, bytes WebAuthnAuth). Otherwise, it
+     * is a PackedUserOperation whose signature field contains the abi-encoded
+     * (bytes ecdsaSignature, bytes WebAuthnAuth).
+     * See https://github.com/Vectorized/solady/blob/v0.1.19/src/utils/WebAuthn.sol
+     * for details on how WebAuthnAuth is encoded.
+     * @param config The node configuration, expected to be abi.encoded as
+     * (address cosigner, bytes32 x, bytes32 y), where cosigner is the ECDSA address
+     * and (x, y) are the WebAuthn public key coordinates.
+     * @return validationData Returns SIG_VALIDATION_SUCCESS (0) if ok, otherwise
+     * SIG_VALIDATION_FAILED (1).
+     */
     function validateData(bytes32 message, bytes calldata data, bytes calldata config)
         external
         view
diff --git a/src/verifier/UserOpWebAuthnVerifier.sol b/src/verifier/UserOpWebAuthnVerifier.sol
index 8dcd766..a39a1d6 100644
--- a/src/verifier/UserOpWebAuthnVerifier.sol
+++ b/src/verifier/UserOpWebAuthnVerifier.sol
@@ -17,6 +17,20 @@ import {OnlyKeystore} from "../lib/OnlyKeystore.sol";
 contract UserOpWebAuthnVerifier is IVerifier, OnlyKeystore {
     constructor(address aKeystore) OnlyKeystore(aKeystore) {}
 
+    /**
+     * @notice Called by the Keystore for nodes with WebAuthn verification.
+     * @param message The hashed message that must be signed by the WebAuthn
+     * authenticator.
+     * @param data The calldata containing the WebAuthn authentication data. If
+     * the data is not a valid WebAuthnAuth struct, it is assumed to be a PackedUserOperation
+     * whose signature field contains the WebAuthnAuth encoded bytes.
+     * See https://github.com/Vectorized/solady/blob/v0.1.19/src/utils/WebAuthn.sol
+     * for details on how WebAuthnAuth is encoded.
+     * @param config The node configuration, expected to be abi.encoded as
+     * (bytes32 x, bytes32 y), where x and y are the WebAuthn public key coordinates.
+     * @return validationData Returns SIG_VALIDATION_SUCCESS (0) if ok, otherwise
+     * SIG_VALIDATION_FAILED (1).
+     */
     function validateData(bytes32 message, bytes calldata data, bytes calldata config)
         external
         view