[router][grpc] Make harmony parser checks recipient first before channel (#12713)

sgl-router/src/routers/grpc/harmony/parser.rs

@@ -106,7 +106,7 @@ impl HarmonyParserAdapter {
     pub fn parse_messages(
         messages: &[openai_harmony::chat::Message],
     ) -> (Option<String>, Option<Vec<ToolCall>>, String) {
-        let mut analysis = None;
+        let mut analysis: Option<String> = None;
         let mut commentary: Option<Vec<ToolCall>> = None;
         let mut final_text = String::new();
 
@@ -119,20 +119,13 @@ impl HarmonyParserAdapter {
             let channel = msg.channel.as_deref().unwrap_or("");
             let recipient = msg.recipient.as_deref();
 
-            match channel {
-                "analysis" => {
-                    // Process each content item
-                    // For Chat API, we join them into a single reasoning_content
-                    let text = Self::extract_text_from_content(&msg.content);
-
-                    if !text.is_empty() {
-                        analysis = Some(text);
-                    }
-                }
-                "commentary" => {
-                    // Handle different recipient types
+            // IMPORTANT: Check recipient FIRST before channel
+            // The model sometimes generates tool calls with channel="analysis" + recipient="functions.*"
+            // instead of channel="commentary" + recipient="functions.*"
+            // We should trust the recipient field to determine if this is a tool call
             if let Some(recipient_str) = recipient {
                 if recipient_str.starts_with("functions.") {
+                    // This is a tool call, regardless of channel
                     let function_name = recipient_str.strip_prefix("functions.").unwrap();
 
                     // Process each content item separately
@@ -154,6 +147,8 @@ impl HarmonyParserAdapter {
                             }
                         }
                     }
+                    // Skip further channel processing for this message
+                    continue;
                 } else if recipient_str.starts_with("python")
                     || recipient_str.starts_with("browser")
                     || recipient_str.starts_with("container")
@@ -172,9 +167,42 @@ impl HarmonyParserAdapter {
                             None => analysis = Some(text),
                         }
                     }
+                    // Skip further channel processing
+                    continue;
+                }
+            }
+
+            // Now process by channel (only if not already handled by recipient)
+            match channel {
+                "analysis" => {
+                    // Process each content item
+                    // For Chat API, we join them into a single reasoning_content
+                    let text = Self::extract_text_from_content(&msg.content);
+
+                    if !text.is_empty() {
+                        analysis = Some(text);
+                    }
+                }
+                "commentary" => {
+                    // If we reach here, recipient was not "functions.*" or built-in tools
+                    // Commentary channel should always have a recipient
+                    // This is likely a model bug - log warning and treat as reasoning
+                    tracing::warn!(
+                        channel = "commentary",
+                        recipient = ?recipient,
+                        "Commentary message without valid recipient, treating as reasoning"
+                    );
+
+                    let text = Self::extract_text_from_content(&msg.content);
+
+                    if !text.is_empty() {
+                        match analysis.as_mut() {
+                            Some(existing) => {
+                                existing.push('\n');
+                                existing.push_str(&text);
+                            }
+                            None => analysis = Some(text),
                         }
-                        // Unknown recipient would raise ValueError
-                        // For now, we silently ignore (can add logging later)
                     }
                 }
                 "final" => {
@@ -215,16 +243,9 @@ impl HarmonyParserAdapter {
     ) -> Result<HarmonyChannelOutput, String> {
         // Feed all tokens to the parser
         for &token_id in output_ids {
-            self.parser.process(token_id).map_err(|e| {
-                // Log the full output_ids context on error
-                tracing::error!(
-                    token_id = token_id,
-                    output_ids = ?output_ids,
-                    error = %e,
-                    "Harmony parser failed to process token"
-                );
-                format!("Failed to process token {}: {}", token_id, e)
-            })?;
+            self.parser
+                .process(token_id)
+                .map_err(|e| format!("Failed to process token {}: {}", token_id, e))?;
         }
 
         // Extract all completed messages from the parser
@@ -240,7 +261,7 @@ impl HarmonyParserAdapter {
         let final_finish_reason = if commentary.is_some() {
             "tool_calls".to_string()
         } else {
-            finish_reason
+            finish_reason.clone()
         };
 
         Ok(HarmonyChannelOutput {