fix: prevent premature loop exit when weak models return empty after substantive tool calls (#10472)

The _last_content_with_tools fallback was firing indiscriminately for ALL
content+tool turns, including mid-task narration alongside substantive
tools (terminal, search_files, etc.).  This caused the agent to exit
the loop with 'I'll scan the directory...' as the final answer instead
of nudging the model to continue processing tool results.

The fix restricts the fallback to housekeeping-only turns (memory, todo,
skill_manage, session_search) where the content genuinely IS the final
answer.  When substantive tools are present, the existing post-tool
nudge mechanism now fires instead, prompting the model to continue.

Affected models: xiaomi/mimo-v2-pro, GLM-5, and other weaker models
that intermittently return empty after tool results.

Reported by user Renaissance on Discord.

run_agent.py

@@ -7881,6 +7881,7 @@ class AIAgent:
         self._thinking_prefill_retries = 0
         self._post_tool_empty_retried = False
         self._last_content_with_tools = None
+        self._last_content_tools_all_housekeeping = False
         self._mute_post_response = False
         self._unicode_sanitization_passes = 0
 
@@ -8068,6 +8069,7 @@ class AIAgent:
                     self._empty_content_retries = 0
                     self._thinking_prefill_retries = 0
                     self._last_content_with_tools = None
+                    self._last_content_tools_all_housekeeping = False
                     self._mute_post_response = False
                     # Re-estimate after compression
                     _preflight_tokens = estimate_request_tokens_rough(
@@ -10130,6 +10132,7 @@ class AIAgent:
                             tc.function.name in _HOUSEKEEPING_TOOLS
                             for tc in assistant_message.tool_calls
                         )
+                        self._last_content_tools_all_housekeeping = _all_housekeeping
                         if _all_housekeeping and self._has_stream_consumers():
                             self._mute_post_response = True
                         elif self.quiet_mode:
@@ -10312,15 +10315,22 @@ class AIAgent:
                             break
 
                         # If the previous turn already delivered real content alongside
-                        # tool calls (e.g. "You're welcome!" + memory save), the model
-                        # has nothing more to say. Use the earlier content immediately
-                        # instead of wasting API calls on retries that won't help.
+                        # HOUSEKEEPING tool calls (e.g. "You're welcome!" + memory save),
+                        # the model has nothing more to say. Use the earlier content
+                        # immediately instead of wasting API calls on retries.
+                        # NOTE: Only use this shortcut when ALL tools in that turn were
+                        # housekeeping (memory, todo, etc.).  When substantive tools
+                        # were called (terminal, search_files, etc.), the content was
+                        # likely mid-task narration ("I'll scan the directory...") and
+                        # the empty follow-up means the model choked — let the
+                        # post-tool nudge below handle that instead of exiting early.
                         fallback = getattr(self, '_last_content_with_tools', None)
-                        if fallback:
+                        if fallback and getattr(self, '_last_content_tools_all_housekeeping', False):
                             _turn_exit_reason = "fallback_prior_turn_content"
                             logger.info("Empty follow-up after tool calls — using prior turn content as final response")
                             self._emit_status("↻ Empty response after tool calls — using earlier content as final answer")
                             self._last_content_with_tools = None
+                            self._last_content_tools_all_housekeeping = False
                             self._empty_content_retries = 0
                             # Do NOT modify the assistant message content — the
                             # old code injected "Calling the X tools..." which
@@ -10331,13 +10341,18 @@ class AIAgent:
                             break
 
                         # ── Post-tool-call empty response nudge ───────────
-                        # The model returned empty after executing tool calls
-                        # but there's no prior-turn content to fall back on.
+                        # The model returned empty after executing tool calls.
+                        # This covers two cases:
+                        #  (a) No prior-turn content at all — model went silent
+                        #  (b) Prior turn had content + SUBSTANTIVE tools (the
+                        #      fallback above was skipped because the content
+                        #      was mid-task narration, not a final answer)
                         # Instead of giving up, nudge the model to continue by
                         # appending a user-level hint.  This is the #9400 case:
-                        # weaker models (GLM-5, etc.) sometimes return empty
-                        # after tool results instead of continuing to the next
-                        # step.  One retry with a nudge usually fixes it.
+                        # weaker models (mimo-v2-pro, GLM-5, etc.) sometimes
+                        # return empty after tool results instead of continuing
+                        # to the next step.  One retry with a nudge usually
+                        # fixes it.
                         _prior_was_tool = any(
                             m.get("role") == "tool"
                             for m in messages[-5:]  # check recent messages
@@ -10347,6 +10362,10 @@ class AIAgent:
                             and not getattr(self, "_post_tool_empty_retried", False)
                         ):
                             self._post_tool_empty_retried = True
+                            # Clear stale narration so it doesn't resurface
+                            # on a later empty response after the nudge.
+                            self._last_content_with_tools = None
+                            self._last_content_tools_all_housekeeping = False
                             logger.info(
                                 "Empty response after tool calls — nudging model "
                                 "to continue processing"