diff --git a/website/docs/language/expressions/custom-conditions.mdx b/website/docs/language/expressions/custom-conditions.mdx
index 42f08343fc..fe9d45849a 100644
--- a/website/docs/language/expressions/custom-conditions.mdx
+++ b/website/docs/language/expressions/custom-conditions.mdx
@@ -341,7 +341,7 @@ The selected AMI must be tagged with the Component value "nomad-server".
 ```
 
 The `error_message` argument can be any expression that evaluates to a string.
-This includes literal strings, heredocs, and template expressions. Multi-line
+This includes literal strings, heredocs, and template expressions. You can use the [`format` function](/language/functions/format) to convert items of `null`, `list`, or `map` types into a formatted string. Multi-line
 error messages are supported, and lines with leading whitespace will not be
 word wrapped.