diff --git a/codex-rs/cloud-tasks/src/util.rs b/codex-rs/cloud-tasks/src/util.rs
index 812d0b4b9a..d041d8ce10 100644
--- a/codex-rs/cloud-tasks/src/util.rs
+++ b/codex-rs/cloud-tasks/src/util.rs
@@ -31,10 +31,7 @@ pub fn append_error_log(message: impl AsRef<str>) {
 /// - trims trailing '/'
 /// - appends '/backend-api' for ChatGPT hosts when missing
 pub fn normalize_base_url(input: &str) -> String {
-    let mut base_url = input.to_string();
-    while base_url.ends_with('/') {
-        base_url.pop();
-    }
+    let mut base_url = input.trim_end_matches('/').to_string();
     if (base_url.starts_with("https://chatgpt.com")
         || base_url.starts_with("https://chat.openai.com"))
         && !base_url.contains("/backend-api")
@@ -171,3 +168,36 @@ pub fn format_relative_time(reference: DateTime<Utc>, ts: DateTime<Utc>) -> Stri
 pub fn format_relative_time_now(ts: DateTime<Utc>) -> String {
     format_relative_time(Utc::now(), ts)
 }
+
+#[cfg(test)]
+mod tests {
+    use pretty_assertions::assert_eq;
+
+    use super::normalize_base_url;
+
+    #[test]
+    fn normalize_base_url_normalizes_urls() {
+        for (input, expected) in [
+            ("https://example.com/path", "https://example.com/path"),
+            ("https://example.com/path/", "https://example.com/path"),
+            ("https://example.com/path///", "https://example.com/path"),
+            ("", ""),
+            ("///", ""),
+            ("https://chatgpt.com///", "https://chatgpt.com/backend-api"),
+            (
+                "https://chatgpt.com/backend-api///",
+                "https://chatgpt.com/backend-api",
+            ),
+            (
+                "https://chat.openai.com///",
+                "https://chat.openai.com/backend-api",
+            ),
+            (
+                "https://chat.openai.com/backend-api///",
+                "https://chat.openai.com/backend-api",
+            ),
+        ] {
+            assert_eq!(normalize_base_url(input), expected, "input: {input:?}");
+        }
+    }
+}