diff --git a/docs/v1/annotations.md b/docs/v1/annotations.md
index 77430be..b0d8c19 100644
--- a/docs/v1/annotations.md
+++ b/docs/v1/annotations.md
@@ -37,3 +37,4 @@ This property contains arbitrary metadata, and SHOULD follow the rules of [OCI i
 - **`org.cnai.model.license`**: Specifies the layer is a LICENSE file (boolean), such as `true` or `false`.
 - **`org.cnai.model.config`**: Specifies the layer is a configuration file (boolean), such as `true` or `false`.
 - **`org.cnai.model.model`**: Specifies the layer is a model file (boolean), such as `true` or `false`.
+- **`org.cnai.model.filepath`**: Specifies the file path of the layer (string).
diff --git a/specs-go/v1/annotations.go b/specs-go/v1/annotations.go
index 914ce68..f6eb237 100644
--- a/specs-go/v1/annotations.go
+++ b/specs-go/v1/annotations.go
@@ -92,4 +92,7 @@ const (
 
 	// AnnotationModel is the annotation key for the layer is a model file (boolean), such as `true` or `false`.
 	AnnotationModel = "org.cnai.model.model"
+
+	// AnnotationFilepath is the annotation key for the file path of the layer.
+	AnnotationFilepath = "org.cnai.model.filepath"
 )