diff --git a/docs/2.guide/2.directory-structure/1.shared.md b/docs/2.guide/2.directory-structure/1.shared.md
index ed8a0654c8..0e29ac48b6 100644
--- a/docs/2.guide/2.directory-structure/1.shared.md
+++ b/docs/2.guide/2.directory-structure/1.shared.md
@@ -21,7 +21,7 @@ Code in the `shared/` directory cannot import any Vue or Nitro code.
 
 ```ts twoslash [shared/utils/capitalize.ts]
 export const capitalize = (input: string) => {
-  return input[0].toUpperCase() + input.slice(1)
+  return input[0] ? input[0].toUpperCase() + input.slice(1) : ''
 }
 ```
 
@@ -29,7 +29,7 @@ export const capitalize = (input: string) => {
 
 ```ts twoslash [shared/utils/capitalize.ts]
 export default function capitalize (input: string) {
-  return input[0].toUpperCase() + input.slice(1)
+  return input[0] ? input[0].toUpperCase() + input.slice(1) : ''
 }
 ```