Revert "fix: ensure reasoning_content on all Kimi assistant+tool_calls messages"

This reverts commit 4238930.

Author: stebbins

crates/goose/src/providers/formats/openai.rs

@@ -836,28 +836,11 @@ pub fn create_request(
         "content": system
     });
 
-    let mut messages_spec = format_messages(messages, image_format);
+    let messages_spec = format_messages(messages, image_format);
     let mut tools_spec = format_tools(tools)?;
 
     validate_tool_schemas(&mut tools_spec);
 
-    // Safety net: Kimi thinking models require reasoning_content on every
-    // assistant message with tool_calls. Add empty reasoning_content if missing,
-    // which handles edge cases where thinking content was stripped by compaction,
-    // tool-pair summarization, or simply not returned by the model.
-    if is_kimi_thinking {
-        for msg in &mut messages_spec {
-            let is_assistant = msg.get("role").and_then(|v| v.as_str()) == Some("assistant");
-            let has_tool_calls = msg.get("tool_calls").is_some();
-            let has_reasoning = msg.get("reasoning_content").is_some();
-            if is_assistant && has_tool_calls && !has_reasoning {
-                msg.as_object_mut()
-                    .unwrap()
-                    .insert("reasoning_content".to_string(), json!(""));
-            }
-        }
-    }
-
     let mut messages_array = vec![system_message];
     messages_array.extend(messages_spec);
 
@@ -2132,50 +2115,4 @@ data: [DONE]
 
         Ok(())
     }
-
-    #[test]
-    fn test_create_request_kimi_ensures_reasoning_content() -> anyhow::Result<()> {
-        let model_config = ModelConfig {
-            model_name: "kimi-k2.5".to_string(),
-            context_limit: Some(131072),
-            temperature: None,
-            max_tokens: None,
-            toolshim: false,
-            toolshim_model: None,
-            fast_model: None,
-            request_params: None,
-        };
-
-        // Create an assistant message with a tool call but NO thinking content.
-        // This simulates edge cases where thinking was stripped (compaction,
-        // tool-pair summarization) or never returned by the model.
-        let msg = Message::assistant().with_tool_request(
-            "call_1",
-            Ok(CallToolRequestParams {
-                meta: None,
-                task: None,
-                name: "test_tool".into(),
-                arguments: Some(object!({"key": "value"})),
-            }),
-        );
-
-        let request = create_request(
-            &model_config,
-            "system",
-            &[Message::user().with_text("hello"), msg],
-            &[],
-            &ImageFormat::OpenAi,
-            false,
-        )?;
-
-        let messages = request["messages"].as_array().unwrap();
-        // messages[0] = system, messages[1] = user, messages[2] = assistant with tool_calls
-        let assistant_msg = &messages[2];
-        assert_eq!(assistant_msg["role"], "assistant");
-        assert!(assistant_msg.get("tool_calls").is_some());
-        // Safety net should have added reasoning_content
-        assert_eq!(assistant_msg.get("reasoning_content").unwrap(), &json!(""));
-
-        Ok(())
-    }
 }