diff --git a/crates/language_models/src/provider/open_ai.rs b/crates/language_models/src/provider/open_ai.rs
index 0894b58fe2048e..20bfdb87b52992 100644
--- a/crates/language_models/src/provider/open_ai.rs
+++ b/crates/language_models/src/provider/open_ai.rs
@@ -384,34 +384,34 @@ impl LanguageModel for OpenAiLanguageModel {
             LanguageModelCompletionError,
         >,
     > {
-        if self.model.supports_chat_completions() {
-            let request = into_open_ai(
+        if self.model.uses_responses_api() {
+            let request = into_open_ai_response(
                 request,
                 self.model.id(),
                 self.model.supports_parallel_tool_calls(),
                 self.model.supports_prompt_cache_key(),
                 self.max_output_tokens(),
                 self.model.reasoning_effort(),
-                false,
             );
-            let completions = self.stream_completion(request, cx);
+            let completions = self.stream_response(request, cx);
             async move {
-                let mapper = OpenAiEventMapper::new();
+                let mapper = OpenAiResponseEventMapper::new();
                 Ok(mapper.map_stream(completions.await?).boxed())
             }
             .boxed()
         } else {
-            let request = into_open_ai_response(
+            let request = into_open_ai(
                 request,
                 self.model.id(),
                 self.model.supports_parallel_tool_calls(),
                 self.model.supports_prompt_cache_key(),
                 self.max_output_tokens(),
                 self.model.reasoning_effort(),
+                false,
             );
-            let completions = self.stream_response(request, cx);
+            let completions = self.stream_completion(request, cx);
             async move {
-                let mapper = OpenAiResponseEventMapper::new();
+                let mapper = OpenAiEventMapper::new();
                 Ok(mapper.map_stream(completions.await?).boxed())
             }
             .boxed()
diff --git a/crates/open_ai/src/open_ai.rs b/crates/open_ai/src/open_ai.rs
index c6edf6b08c8fc9..b8fad3730d7ce7 100644
--- a/crates/open_ai/src/open_ai.rs
+++ b/crates/open_ai/src/open_ai.rs
@@ -266,17 +266,12 @@ impl Model {
         }
     }
 
-    pub fn supports_chat_completions(&self) -> bool {
+    pub fn uses_responses_api(&self) -> bool {
         match self {
             Self::Custom {
                 supports_chat_completions,
                 ..
-            } => *supports_chat_completions,
-            Self::FiveCodex
-            | Self::FivePointTwoCodex
-            | Self::FivePointThreeCodex
-            | Self::FivePointFourPro
-            | Self::FivePointFivePro => false,
+            } => !*supports_chat_completions,
             _ => true,
         }
     }