diff --git a/crates/typst-library/src/foundations/str.rs b/crates/typst-library/src/foundations/str.rs
index 5a939fdba..8ac99ac63 100644
--- a/crates/typst-library/src/foundations/str.rs
+++ b/crates/typst-library/src/foundations/str.rs
@@ -575,6 +575,11 @@ impl Str {
 
     /// Splits a string at matches of a specified pattern and returns an array
     /// of the resulting parts.
+    ///
+    /// When the empty string is used as a separator, it separates every
+    /// character in the string, along with the beginning and end of the
+    /// string. In practice, this means that the resulting list of parts
+    /// will contain the empty string at the start and end of the list.
     #[func]
     pub fn split(
         &self,