Index: lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/lldbvscode_testcase.py
===================================================================
--- lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/lldbvscode_testcase.py
+++ lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/lldbvscode_testcase.py
@@ -132,15 +132,29 @@
                                     key, key_path, d))
         return value
 
-    def get_stackFrames(self, threadId=None, startFrame=None, levels=None,
-                        dump=False):
+    def get_stackFrames_and_totalFramesCount(self, threadId=None, startFrame=None, 
+                        levels=None, dump=False):
         response = self.vscode.request_stackTrace(threadId=threadId,
                                                   startFrame=startFrame,
                                                   levels=levels,
                                                   dump=dump)
         if response:
-            return self.get_dict_value(response, ['body', 'stackFrames'])
-        return None
+            stackFrames = self.get_dict_value(response, ['body', 'stackFrames'])
+            totalFrames = self.get_dict_value(response, ['body', 'totalFrames'])
+            self.assertTrue(totalFrames > 0,
+                    'verify totalFrames count is provided by extension that supports '
+                    'async frames loading')
+            return (stackFrames, totalFrames)
+        return (None, 0)
+
+    def get_stackFrames(self, threadId=None, startFrame=None, levels=None,
+                        dump=False):
+        (stackFrames, totalFrames) = self.get_stackFrames_and_totalFramesCount(
+                                                threadId=threadId,
+                                                startFrame=startFrame,
+                                                levels=levels,
+                                                dump=dump)
+        return stackFrames
 
     def get_source_and_line(self, threadId=None, frameIndex=0):
         stackFrames = self.get_stackFrames(threadId=threadId,
Index: lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/stackTrace/TestVSCode_stackTrace.py
===================================================================
--- lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/stackTrace/TestVSCode_stackTrace.py
+++ lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/stackTrace/TestVSCode_stackTrace.py
@@ -76,10 +76,12 @@
         self.continue_to_breakpoints(breakpoint_ids)
         startFrame = 0
         # Verify we get all stack frames with no arguments
-        stackFrames = self.get_stackFrames()
+        (stackFrames, totalFrames) = self.get_stackFrames_and_totalFramesCount()
         frameCount = len(stackFrames)
         self.assertTrue(frameCount >= 20,
                         'verify we get at least 20 frames for all frames')
+        self.assertTrue(totalFrames == frameCount,
+                        'verify we get correct value for totalFrames count')
         self.verify_stackFrames(startFrame, stackFrames)
 
         # Verify all stack frames by specifying startFrame = 0 and levels not
@@ -133,11 +135,15 @@
         # Verify we cap things correctly when we ask for too many frames
         startFrame = 5
         levels = 1000
-        stackFrames = self.get_stackFrames(startFrame=startFrame,
-                                           levels=levels)
+        (stackFrames, totalFrames) = self.get_stackFrames_and_totalFramesCount(
+                                            startFrame=startFrame,
+                                            levels=levels)
         self.assertTrue(len(stackFrames) == frameCount - startFrame,
                         ('verify less than 1000 frames with startFrame=%i and'
                          ' levels=%i') % (startFrame, levels))
+        self.assertTrue(totalFrames == frameCount,
+                        'verify we get correct value for totalFrames count '
+                        'when requested frames not from 0 index')
         self.verify_stackFrames(startFrame, stackFrames)
 
         # Verify level=0 works with non-zerp start frame
Index: lldb/tools/lldb-vscode/lldb-vscode.cpp
===================================================================
--- lldb/tools/lldb-vscode/lldb-vscode.cpp
+++ lldb/tools/lldb-vscode/lldb-vscode.cpp
@@ -2166,6 +2166,8 @@
         break;
       stackFrames.emplace_back(CreateStackFrame(frame));
     }
+    const auto totalFrames = thread.GetNumFrames();
+    body.try_emplace("totalFrames", totalFrames);
   }
   body.try_emplace("stackFrames", std::move(stackFrames));
   response.try_emplace("body", std::move(body));