diff --git a/rpc/interface/src/route/bin.rs b/rpc/interface/src/route/bin.rs
index 1e3b202..12c4e57 100644
--- a/rpc/interface/src/route/bin.rs
+++ b/rpc/interface/src/route/bin.rs
@@ -71,12 +71,13 @@ macro_rules! generate_endpoints_inner {
     ($variant:ident, $handler:ident, $request:expr_2021) => {
         paste::paste! {
             {
-                // INVARIANT:
-                // The handler functions in `cuprated` depend on this line existing,
-                // the functions themselves do not check if they are being called
-                // from an (un)restricted context.
+                // Check if restricted.
                 //
-                // This line must be here or all methods will be allowed to be called freely.
+                // INVARIANT:
+                // The RPC handler functions in `cuprated` depend on this line existing,
+                // the functions themselves do not check if they are being called
+                // from an (un)restricted context. This line must be here or all
+                // methods will be allowed to be called freely.
                 if [<$variant Request>]::IS_RESTRICTED && $handler.is_restricted() {
                     // TODO: mimic `monerod` behavior.
                     return Err(StatusCode::FORBIDDEN);
diff --git a/rpc/interface/src/route/json_rpc.rs b/rpc/interface/src/route/json_rpc.rs
index 1ef5722..9d814c2 100644
--- a/rpc/interface/src/route/json_rpc.rs
+++ b/rpc/interface/src/route/json_rpc.rs
@@ -39,21 +39,16 @@ pub(crate) async fn json_rpc<H: RpcHandler>(
     // the requested method is only for non-restricted RPC.
     //
     // INVARIANT:
-    // The handler functions in `cuprated` depend on this line existing,
+    // The RPC handler functions in `cuprated` depend on this line existing,
     // the functions themselves do not check if they are being called
-    // from an (un)restricted context.
-    //
-    // This line must be here or all methods will be allowed to be called freely.
+    // from an (un)restricted context. This line must be here or all
+    // methods will be allowed to be called freely.
     if request.body.is_restricted() && handler.is_restricted() {
-        let error_object = ErrorObject {
-            code: ErrorCode::ServerError(-1 /* TODO */),
-            message: Cow::Borrowed("Restricted. TODO: mimic monerod message"),
-            data: None,
-        };
-
-        let response = Response::err(id, error_object);
-
-        return Ok(Json(response));
+        // The error when a restricted JSON-RPC method is called as per:
+        //
+        // - <https://github.com/monero-project/monero/blob/893916ad091a92e765ce3241b94e706ad012b62a/contrib/epee/include/net/http_server_handlers_map2.h#L244-L252>
+        // - <https://github.com/monero-project/monero/blob/cc73fe71162d564ffda8e549b79a350bca53c454/src/rpc/core_rpc_server.h#L188>
+        return Ok(Json(Response::method_not_found(id)));
     }
 
     // Send request.
diff --git a/rpc/interface/src/route/other.rs b/rpc/interface/src/route/other.rs
index 2b7c14b..3a804a6 100644
--- a/rpc/interface/src/route/other.rs
+++ b/rpc/interface/src/route/other.rs
@@ -77,11 +77,10 @@ macro_rules! generate_endpoints_inner {
                 // Check if restricted.
                 //
                 // INVARIANT:
-                // The handler functions in `cuprated` depend on this line existing,
+                // The RPC handler functions in `cuprated` depend on this line existing,
                 // the functions themselves do not check if they are being called
-                // from an (un)restricted context.
-                //
-                // This line must be here or all methods will be allowed to be called freely.
+                // from an (un)restricted context. This line must be here or all
+                // methods will be allowed to be called freely.
                 if [<$variant Request>]::IS_RESTRICTED && $handler.is_restricted() {
                     // TODO: mimic `monerod` behavior.
                     return Err(StatusCode::FORBIDDEN);