diff --git a/src/json.c b/src/json.c
index 31bac26..8d9a03b 100644
--- a/src/json.c
+++ b/src/json.c
@@ -183,6 +183,7 @@
 
 	case VAR_FUNC:
 	case VAR_JOB:
+	case VAR_CHANNEL:
 	    /* no JSON equivalent TODO: better error */
 	    EMSG(_(e_invarg));
 	    return FAIL;