Follow-up from #16542

crates/uv-python/src/installation.rs

@@ -107,12 +107,14 @@ impl PythonInstallation {
     ) -> Result<Self, Error> {
         let request = request.unwrap_or(&PythonRequest::Default);
 
+        let client = client_builder.build();
+        let download_list =
+            ManagedPythonDownloadList::new(&client, python_downloads_json_url).await?;
+
         // Python downloads are performing their own retries to catch stream errors, disable the
         // default retries to avoid the middleware performing uncontrolled retries.
         let retry_policy = client_builder.retry_policy();
         let client = client_builder.clone().retries(0).build();
-        let download_list =
-            ManagedPythonDownloadList::new(&client, python_downloads_json_url).await?;
 
         // Search for the installation
         let err = match Self::find(

crates/uv/src/commands/pip/compile.rs

@@ -294,7 +294,7 @@ pub(crate) async fn pip_compile(
     // Find an interpreter to use for building distributions
     let environment_preference = EnvironmentPreference::from_system_flag(system, false);
     let python_preference = python_preference.with_system_flag(system);
-    let client = client_builder.clone().retries(0).build();
+    let client = client_builder.build();
     let download_list = ManagedPythonDownloadList::new(
         &client,
         install_mirrors.python_downloads_json_url.as_deref(),

crates/uv/src/commands/python/find.rs

@@ -77,7 +77,7 @@ pub(crate) async fn find(
     )
     .await?;
 
-    let client = client_builder.clone().retries(0).build();
+    let client = client_builder.build();
     let download_list = ManagedPythonDownloadList::new(&client, python_downloads_json_url).await?;
 
     let python = PythonInstallation::find(

crates/uv/src/commands/python/pin.rs

@@ -97,7 +97,7 @@ pub(crate) async fn pin(
             for pin in file.versions() {
                 writeln!(printer.stdout(), "{}", pin.to_canonical_string())?;
                 if let Some(virtual_project) = &virtual_project {
-                    let client = client_builder.clone().retries(0).build();
+                    let client = client_builder.build();
                     let download_list = ManagedPythonDownloadList::new(
                         &client,
                         install_mirrors.python_downloads_json_url.as_deref(),

crates/uv/tests/it/network.rs

@@ -421,3 +421,59 @@ async fn rfc9457_problem_details_license_violation() {
       ╰─▶ HTTP status client error (403 Forbidden) for url ([SERVER]/packages/tqdm-4.67.1-py3-none-any.whl)
     ");
 }
+
+/// Check the python list error message when the server returns HTTP status 500, a retryable error.
+#[tokio::test]
+async fn python_list_remote_python_downloads_json_url_http_500() {
+    let context = TestContext::new("3.12");
+
+    let (_server_drop_guard, mock_server_uri) = http_error_server().await;
+
+    let python_downloads_json_url = format!("{mock_server_uri}/python_downloads.json");
+    let filters = vec![(mock_server_uri.as_str(), "[SERVER]")];
+    uv_snapshot!(filters, context
+        .python_list()
+        .arg("--python-downloads-json-url")
+        .arg(&python_downloads_json_url)
+        .env_remove(EnvVars::UV_HTTP_RETRIES)
+        .env(EnvVars::UV_TEST_NO_HTTP_RETRY_DELAY, "true"), @r"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    error: Error while fetching remote python downloads json from '[SERVER]/python_downloads.json'
+      Caused by: Request failed after 3 retries
+      Caused by: Failed to download [SERVER]/python_downloads.json
+      Caused by: HTTP status server error (500 Internal Server Error) for url ([SERVER]/python_downloads.json)
+    ");
+}
+
+/// Check the python list error message when the server returns a retryable IO error.
+#[tokio::test]
+async fn python_list_remote_python_downloads_json_url_io_error() {
+    let context = TestContext::new("3.12");
+
+    let (_server_drop_guard, mock_server_uri) = io_error_server().await;
+
+    let python_downloads_json_url = format!("{mock_server_uri}/python_downloads.json");
+    let filters = vec![(mock_server_uri.as_str(), "[SERVER]")];
+    uv_snapshot!(filters, context
+        .python_list()
+        .arg("--python-downloads-json-url")
+        .arg(&python_downloads_json_url)
+        .env_remove(EnvVars::UV_HTTP_RETRIES)
+        .env(EnvVars::UV_TEST_NO_HTTP_RETRY_DELAY, "true"), @r"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    error: Error while fetching remote python downloads json from '[SERVER]/python_downloads.json'
+      Caused by: Failed to download [SERVER]/python_downloads.json
+      Caused by: Request failed after 3 retries
+      Caused by: error sending request for url ([SERVER]/python_downloads.json)
+      Caused by: client error (SendRequest)
+      Caused by: connection closed before message completed
+    ");
+}