diff --git a/src/commands.c b/src/commands.c
index 63dfd92e37..07f09bc15b 100644
--- a/src/commands.c
+++ b/src/commands.c
@@ -3352,8 +3352,8 @@ struct redisCommandArg EVAL_RO_Args[] = {
 struct redisCommandArg FCALL_Args[] = {
 {"function",ARG_TYPE_STRING,-1,NULL,NULL,NULL,CMD_ARG_NONE},
 {"numkeys",ARG_TYPE_INTEGER,-1,NULL,NULL,NULL,CMD_ARG_NONE},
-{"key",ARG_TYPE_KEY,0,NULL,NULL,NULL,CMD_ARG_MULTIPLE},
-{"arg",ARG_TYPE_STRING,-1,NULL,NULL,NULL,CMD_ARG_MULTIPLE},
+{"key",ARG_TYPE_KEY,0,NULL,NULL,NULL,CMD_ARG_OPTIONAL|CMD_ARG_MULTIPLE},
+{"arg",ARG_TYPE_STRING,-1,NULL,NULL,NULL,CMD_ARG_OPTIONAL|CMD_ARG_MULTIPLE},
 {0}
 };
 
@@ -3369,8 +3369,8 @@ struct redisCommandArg FCALL_Args[] = {
 struct redisCommandArg FCALL_RO_Args[] = {
 {"function",ARG_TYPE_STRING,-1,NULL,NULL,NULL,CMD_ARG_NONE},
 {"numkeys",ARG_TYPE_INTEGER,-1,NULL,NULL,NULL,CMD_ARG_NONE},
-{"key",ARG_TYPE_KEY,0,NULL,NULL,NULL,CMD_ARG_MULTIPLE},
-{"arg",ARG_TYPE_STRING,-1,NULL,NULL,NULL,CMD_ARG_MULTIPLE},
+{"key",ARG_TYPE_KEY,0,NULL,NULL,NULL,CMD_ARG_OPTIONAL|CMD_ARG_MULTIPLE},
+{"arg",ARG_TYPE_STRING,-1,NULL,NULL,NULL,CMD_ARG_OPTIONAL|CMD_ARG_MULTIPLE},
 {0}
 };
 
diff --git a/src/commands/fcall.json b/src/commands/fcall.json
index 27b7b4e353..9e7a905ecd 100644
--- a/src/commands/fcall.json
+++ b/src/commands/fcall.json
@@ -52,11 +52,13 @@
                 "name": "key",
                 "type": "key",
                 "key_spec_index": 0,
+                "optional": true,
                 "multiple": true
             },
             {
                 "name": "arg",
                 "type": "string",
+                "optional": true,
                 "multiple": true
             }
         ]
diff --git a/src/commands/fcall_ro.json b/src/commands/fcall_ro.json
index 46085ebb02..6ba2736c07 100644
--- a/src/commands/fcall_ro.json
+++ b/src/commands/fcall_ro.json
@@ -51,11 +51,13 @@
                 "name": "key",
                 "type": "key",
                 "key_spec_index": 0,
+                "optional": true,
                 "multiple": true
             },
             {
                 "name": "arg",
                 "type": "string",
+                "optional": true,
                 "multiple": true
             }
         ]