diff --git a/app/ui/app/src/api.ts b/app/ui/app/src/api.ts
index c8b2e116..4158bafc 100644
--- a/app/ui/app/src/api.ts
+++ b/app/ui/app/src/api.ts
@@ -205,6 +205,13 @@ export async function* sendMessage(
     data: uint8ArrayToBase64(att.data),
   }));
 
+  // Only send think parameter when actually requesting thinking
+  // Don't send false as it causes issues with some providers
+  const shouldSendThink =
+    think !== undefined &&
+    ((typeof think === "boolean" && think) ||
+      (typeof think === "string" && think !== ""));
+
   const response = await fetch(`${API_BASE}/api/v1/chat/${chatId}`, {
     method: "POST",
     headers: {
@@ -222,7 +229,7 @@ export async function* sendMessage(
         web_search: webSearch ?? false,
         file_tools: fileTools ?? false,
         ...(forceUpdate !== undefined ? { forceUpdate } : {}),
-        ...(think !== undefined ? { think } : {}),
+        ...(shouldSendThink ? { think } : {}),
       }),
     ),
     signal,
diff --git a/app/ui/ui.go b/app/ui/ui.go
index a05ecf0f..1d0e2579 100644
--- a/app/ui/ui.go
+++ b/app/ui/ui.go
@@ -782,25 +782,6 @@ func (s *Server) chat(w http.ResponseWriter, r *http.Request) error {
 	var thinkValue any
 
 	if req.Think != nil {
-		// Validate that the model supports thinking if requested
-		thinkRequested := false
-		switch v := req.Think.(type) {
-		case bool:
-			thinkRequested = v
-		case string:
-			thinkRequested = v != "" && v != "none"
-		}
-
-		if thinkRequested && !think {
-			errorEvent := responses.ErrorEvent{
-				EventName: "error",
-				Error:     fmt.Sprintf("Model %q does not support thinking/reasoning", req.Model),
-				Code:      "model_capability_error",
-			}
-			json.NewEncoder(w).Encode(errorEvent)
-			flusher.Flush()
-			return nil
-		}
 		thinkValue = req.Think
 	} else {
 		thinkValue = think