diff --git a/tools/search.go b/tools/search.go
index 7a0422d..c96f407 100644
--- a/tools/search.go
+++ b/tools/search.go
@@ -49,7 +49,7 @@
 			},
 			"corpus": map[string]interface{}{
 				"type":        "string",
-				"description": "Virtual corpus to search in",
+				"description": "Virtual corpus query to filter search results (optional, when not provided searches all available data)",
 			},
 			"count": map[string]interface{}{
 				"type":        "integer",