diff --git a/src/providers/deepseek.rs b/src/providers/deepseek.rs
index 04993597..e7bff573 100644
--- a/src/providers/deepseek.rs
+++ b/src/providers/deepseek.rs
@@ -57,7 +57,17 @@ impl super::Provider for DeepSeekProvider {
 
     async fn chat_completion(&self, request: UnifiedRequest) -> Result<ProviderResponse, AppError> {
         let messages_json = helpers::messages_to_openai_json(&request.messages).await?;
-        let body = helpers::build_openai_body(&request, messages_json, false);
+        let mut body = helpers::build_openai_body(&request, messages_json, false);
+
+        // Sanitize for deepseek-reasoner
+        if request.model == "deepseek-reasoner" {
+            if let Some(obj) = body.as_object_mut() {
+                obj.remove("tools");
+                obj.remove("tool_choice");
+                obj.remove("temperature");
+                obj.remove("top_p");
+            }
+        }
 
         let response = self
             .client
@@ -114,7 +124,23 @@ impl super::Provider for DeepSeekProvider {
         // DeepSeek doesn't support images in streaming, use text-only
         let messages_json = helpers::messages_to_openai_json_text_only(&request.messages).await?;
         let mut body = helpers::build_openai_body(&request, messages_json, true);
-        body.as_object_mut().expect("body is object").remove("stream_options");
+
+        // DeepSeek reasoning model doesn't support stream_options
+        if request.model == "deepseek-reasoner" {
+            if let Some(obj) = body.as_object_mut() {
+                obj.remove("stream_options");
+                // Also does not support tools/temperature/top_p
+                obj.remove("tools");
+                obj.remove("tool_choice");
+                obj.remove("temperature");
+                obj.remove("top_p");
+            }
+        } else {
+            // For standard deepseek-chat, keep it clean
+            if let Some(obj) = body.as_object_mut() {
+                obj.remove("stream_options");
+            }
+        }
 
         let es = reqwest_eventsource::EventSource::new(
             self.client