diff --git a/elasticsearch/src/lib.rs b/elasticsearch/src/lib.rs
index 92409b94..f00850f8 100644
--- a/elasticsearch/src/lib.rs
+++ b/elasticsearch/src/lib.rs
@@ -188,6 +188,7 @@
 //! let response = client
 //!     .cat()
 //!     .indices(CatIndicesParts::Index(&["*"]))
+//!     .format("json")
 //!     .send()
 //!     .await?;
 //!