diff --git a/codex-rs/core/src/model_provider_info.rs b/codex-rs/core/src/model_provider_info.rs
index 2850996dcf..f83bfdf26e 100644
--- a/codex-rs/core/src/model_provider_info.rs
+++ b/codex-rs/core/src/model_provider_info.rs
@@ -274,7 +274,7 @@ pub fn built_in_model_providers() -> HashMap<String, ModelProviderInfo> {
                     .filter(|v| !v.trim().is_empty()),
                 env_key: None,
                 env_key_instructions: None,
-                wire_api: WireApi::Responses,
+                wire_api: WireApi::Chat,
                 query_params: None,
                 http_headers: Some(
                     [("version".to_string(), env!("CARGO_PKG_VERSION").to_string())]