diff --git a/crates/milli/src/vector/rest.rs b/crates/milli/src/vector/rest.rs
index 9477959ad..41e8ca9f9 100644
--- a/crates/milli/src/vector/rest.rs
+++ b/crates/milli/src/vector/rest.rs
@@ -561,6 +561,7 @@ impl Request {
             Err(error) => {
                 let message =
                     error.error_message("request", REQUEST_PLACEHOLDER, REPEAT_PLACEHOLDER);
+                let message = format!("{message}\n  - Note: this template is using a document template, and so expects to contain the placeholder {REQUEST_PLACEHOLDER:?} rather than {REQUEST_FRAGMENT_PLACEHOLDER:?}");
                 return Err(NewEmbedderError::rest_could_not_parse_template(message));
             }
         };
@@ -592,15 +593,23 @@ impl RequestFromFragments {
         request: Value,
         search_fragments: impl IntoIterator<Item = (String, Value)>,
     ) -> Result<Self, NewEmbedderError> {
-        let request =
-            match InjectableValue::new(request, REQUEST_FRAGMENT_PLACEHOLDER, REPEAT_PLACEHOLDER) {
-                Ok(template) => template,
-                Err(error) => {
-                    let message =
-                        error.error_message("request", REQUEST_PLACEHOLDER, REPEAT_PLACEHOLDER);
-                    return Err(NewEmbedderError::rest_could_not_parse_template(message));
-                }
-            };
+        let request = match InjectableValue::new(
+            request,
+            REQUEST_FRAGMENT_PLACEHOLDER,
+            REPEAT_PLACEHOLDER,
+        ) {
+            Ok(template) => template,
+            Err(error) => {
+                let message = error.error_message(
+                    "request",
+                    REQUEST_FRAGMENT_PLACEHOLDER,
+                    REPEAT_PLACEHOLDER,
+                );
+                let message = format!("{message}\n  - Note: this template is using fragments, and so expects to contain the placeholder {REQUEST_FRAGMENT_PLACEHOLDER:?} rathern than {REQUEST_PLACEHOLDER:?}");
+
+                return Err(NewEmbedderError::rest_could_not_parse_template(message));
+            }
+        };
 
         let search_fragments: Result<_, NewEmbedderError> = search_fragments
             .into_iter()