diff --git a/dvc/schema.py b/dvc/schema.py
index ca7b12bd3..68d102019 100644
--- a/dvc/schema.py
+++ b/dvc/schema.py
@@ -53,6 +53,7 @@ OUT_PSTAGE_DETAILED_SCHEMA = {
         **ANNOTATION_SCHEMA,  # type: ignore[arg-type]
         Output.PARAM_CACHE: bool,
         Output.PARAM_PERSIST: bool,
+        "checkpoint": bool,
         Output.PARAM_REMOTE: str,
         Output.PARAM_PUSH: bool,
     }