diff --git a/aider/coders/base_coder.py b/aider/coders/base_coder.py
index 3bb929216..4b7d0faf4 100755
--- a/aider/coders/base_coder.py
+++ b/aider/coders/base_coder.py
@@ -37,6 +37,11 @@ class ExhaustedContextWindow(Exception):
     pass
 
 
+class ReflectMessage(Exception):
+    def __init__(self, message):
+        super().__init__(message)
+
+
 def wrap_fence(name):
     return f"<{name}>", f"</{name}>"
 
@@ -54,6 +59,7 @@ class Coder:
     last_keyboard_interrupt = None
     max_apply_update_errors = 3
     edit_format = None
+    yield_stream = False
 
     @classmethod
     def create(
@@ -405,6 +411,9 @@ class Coder:
         return {"role": "user", "content": image_messages}
 
     def run(self, with_message=None):
+        list(self.run_stream(with_message))
+
+    def run_stream(self, with_message=None):
         while True:
             try:
                 if with_message:
@@ -414,7 +423,12 @@ class Coder:
                     new_user_message = self.run_loop()
 
                 while new_user_message:
-                    new_user_message = self.send_new_user_message(new_user_message)
+                    try:
+                        for chunk in self.send_new_user_message(new_user_message):
+                            yield chunk
+                        new_user_message = None
+                    except ReflectMessage as msg:
+                        new_user_message = str(msg)
 
                 if with_message:
                     return self.partial_response_content
@@ -495,7 +509,10 @@ class Coder:
 
         self.check_for_file_mentions(inp)
 
-        return self.send_new_user_message(inp)
+        try:
+            list(self.send_new_user_message(inp))
+        except ReflectMessage as msg:
+            return str(msg)
 
     def fmt_system_prompt(self, prompt):
         prompt = prompt.format(fence=self.fence)
@@ -550,7 +567,10 @@ class Coder:
         exhausted = False
         interrupted = False
         try:
-            interrupted = self.send(messages, functions=self.functions)
+            for chunk in self.send(messages, functions=self.functions):
+                yield chunk
+        except KeyboardInterrupt:
+            interrupted = True
         except ExhaustedContextWindow:
             exhausted = True
         except openai.BadRequestError as err:
@@ -579,18 +599,17 @@ class Coder:
         else:
             content = ""
 
+        self.io.tool_output()
+
         if interrupted:
             content += "\n^C KeyboardInterrupt"
-
-        self.io.tool_output()
-        if interrupted:
             self.cur_messages += [dict(role="assistant", content=content)]
             return
 
         edited, edit_error = self.apply_updates()
         if edit_error:
             self.update_cur_messages(set())
-            return edit_error
+            raise ReflectMessage(edit_error)
 
         self.update_cur_messages(edited)
 
@@ -606,7 +625,7 @@ class Coder:
 
         add_rel_files_message = self.check_for_file_mentions(content)
         if add_rel_files_message:
-            return add_rel_files_message
+            raise ReflectMessage(add_rel_files_message)
 
     def update_cur_messages(self, edited):
         if self.partial_response_content:
@@ -674,7 +693,8 @@ class Coder:
             self.chat_completion_call_hashes.append(hash_object.hexdigest())
 
             if self.stream:
-                self.show_send_output_stream(completion)
+                for chunk in self.show_send_output_stream(completion):
+                    yield chunk
             else:
                 self.show_send_output(completion)
         except KeyboardInterrupt:
@@ -689,7 +709,8 @@ class Coder:
             if args:
                 self.io.ai_output(json.dumps(args, indent=4))
 
-        return interrupted
+        if interrupted:
+            raise KeyboardInterrupt
 
     def show_send_output(self, completion):
         if self.verbose:
@@ -790,6 +811,7 @@ class Coder:
                 elif text:
                     sys.stdout.write(text)
                     sys.stdout.flush()
+                    yield text
         finally:
             if mdstream:
                 self.live_incremental_response(mdstream, True)
diff --git a/aider/gui.py b/aider/gui.py
index 4c91bcffe..788805acb 100755
--- a/aider/gui.py
+++ b/aider/gui.py
@@ -270,16 +270,13 @@ class GUI:
         with self.messages.chat_message("user"):
             st.write(prompt)
 
-        res = self.coder.run(prompt)
-        # self.coder.io.user_input(with_message)
-
-        st.session_state.messages.append({"role": "assistant", "content": res})
-
         with self.messages.chat_message("assistant"):
-            st.write(res)
+            res = st.write(self.coder.run_stream(prompt))
             cost = random.random() * 0.003 + 0.001
             st.caption(f"${cost:0.4f}")
 
+        st.session_state.messages.append({"role": "assistant", "content": res})
+
         with self.messages:
             self.mock_tool_output()