diff --git a/docs/api.md b/docs/api.md
index c25763e1..7aeed4d0 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -73,7 +73,7 @@ The support information looks like this:
 {
   languages: Array<{
     name: string,
-    since: string,
+    since?: string,
     parsers: string[],
     group?: string,
     tmScope: string,