fix(agent): honor configured model max tokens

run_agent.py

@@ -1901,8 +1901,35 @@ class AIAgent:
                 _aux_context_config = None
         self._aux_compression_context_length_config = _aux_context_config
 
-        # Read explicit context_length override from model config
+        # Read explicit model output-token override from config when the
+        # caller did not pass one directly.
         _model_cfg = _agent_cfg.get("model", {})
+        if self.max_tokens is None and isinstance(_model_cfg, dict):
+            _config_max_tokens = _model_cfg.get("max_tokens")
+            if _config_max_tokens is not None:
+                try:
+                    if isinstance(_config_max_tokens, bool):
+                        raise ValueError
+                    _parsed_max_tokens = int(_config_max_tokens)
+                    if _parsed_max_tokens <= 0:
+                        raise ValueError
+                    self.max_tokens = _parsed_max_tokens
+                except (TypeError, ValueError):
+                    logger.warning(
+                        "Invalid model.max_tokens in config.yaml: %r — "
+                        "must be a positive integer (e.g. 4096). "
+                        "Falling back to provider default.",
+                        _config_max_tokens,
+                    )
+                    print(
+                        f"\n⚠ Invalid model.max_tokens in config.yaml: {_config_max_tokens!r}\n"
+                        f"  Must be a positive integer (e.g. 4096).\n"
+                        f"  Falling back to provider default.\n",
+                        file=sys.stderr,
+                    )
+        self._session_init_model_config["max_tokens"] = self.max_tokens
+
+        # Read explicit context_length override from model config
         if isinstance(_model_cfg, dict):
             _config_context_length = _model_cfg.get("context_length")
         else: