Skip codex tool-call transcripts in realtime handoff

Stop copying Codex tool-call arguments into realtime handoff input transcripts so delegated text only comes from the tool-call transcription path.

Co-authored-by: Codex <noreply@openai.com>

codex-rs/codex-api/src/endpoint/realtime_websocket/methods.rs

@@ -783,7 +783,7 @@ mod tests {
             Some(RealtimeEvent::HandoffRequested(RealtimeHandoffRequested {
                 handoff_id: "call_123".to_string(),
                 item_id: "item_123".to_string(),
-                input_transcript: "delegate this".to_string(),
+                input_transcript: String::new(),
                 active_transcript: Vec::new(),
             }))
         );
@@ -905,7 +905,7 @@ mod tests {
             Some(RealtimeEvent::HandoffRequested(RealtimeHandoffRequested {
                 handoff_id: "call_123".to_string(),
                 item_id: "item_123".to_string(),
-                input_transcript: "delegate from done".to_string(),
+                input_transcript: String::new(),
                 active_transcript: Vec::new(),
             }))
         );

codex-rs/codex-api/src/endpoint/realtime_websocket/protocol_v2.rs

@@ -14,7 +14,6 @@ use tracing::debug;
 const CODEX_TOOL_NAME: &str = "codex";
 const DEFAULT_AUDIO_SAMPLE_RATE: u32 = 24_000;
 const DEFAULT_AUDIO_CHANNELS: u16 = 1;
-const TOOL_ARGUMENT_KEYS: [&str; 5] = ["input_transcript", "input", "text", "prompt", "query"];
 
 pub(super) fn parse_realtime_event_v2(payload: &str) -> Option<RealtimeEvent> {
     let (parsed, message_type) = parse_realtime_payload(payload, "realtime v2")?;
@@ -161,28 +160,7 @@ fn parse_handoff_requested_event(item: &JsonMap<String, Value>) -> Option<Realti
     Some(RealtimeEvent::HandoffRequested(RealtimeHandoffRequested {
         handoff_id: call_id.to_string(),
         item_id,
-        input_transcript: extract_input_transcript(arguments),
+        input_transcript: String::new(),
         active_transcript: Vec::new(),
     }))
 }
-
-fn extract_input_transcript(arguments: &str) -> String {
-    if arguments.is_empty() {
-        return String::new();
-    }
-
-    if let Ok(arguments_json) = serde_json::from_str::<Value>(arguments)
-        && let Some(arguments_object) = arguments_json.as_object()
-    {
-        for key in TOOL_ARGUMENT_KEYS {
-            if let Some(value) = arguments_object.get(key).and_then(Value::as_str) {
-                let trimmed = value.trim();
-                if !trimmed.is_empty() {
-                    return trimmed.to_string();
-                }
-            }
-        }
-    }
-
-    arguments.to_string()
-}

codex-rs/codex-api/tests/realtime_websocket_e2e.rs

@@ -450,7 +450,7 @@ async fn realtime_ws_e2e_realtime_v2_parser_emits_handoff_requested() {
         RealtimeEvent::HandoffRequested(RealtimeHandoffRequested {
             handoff_id: "call_123".to_string(),
             item_id: "item_123".to_string(),
-            input_transcript: "delegate now".to_string(),
+            input_transcript: String::new(),
             active_transcript: Vec::new(),
         })
     );