fix(subagents): raise general-purpose max_turns to 150 and default timeout to 30min (#3610)

* fix(subagents): raise general-purpose max_turns to 150 and default timeout to 30min

Deep-research subtasks failed out of the box with GraphRecursionError (Recursion limit of 100 reached): the built-in general-purpose subagent caps at max_turns=100. Raise it to 150 and bump the default subagent timeout from 900s (15min) to 1800s (30min) so the extra turns have time to run instead of shifting the failure to a timeout. The lead agent recursion_limit (100) is unchanged; the failures are subagent-only.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(subagents): clarify lead recursion_limit is independent of subagent max_turns

Add comments at both lead recursion_limit=100 sites (gateway services + channel manager) explaining the lead's LangGraph super-step budget is separate from subagent depth, so the two 100s are not conflated. Comment-only, no behavior change.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(subagents): clarify built-in vs custom timeout scope; pin bash max_turns in test

Review follow-ups: (1) clarify SubagentConfig docstring + global timeout field/comment that the 1800 default applies to built-in subagents (custom agents keep their own timeout_seconds); (2) pin bash.max_turns==60 in the defaults regression test so the config.example.yaml doc cannot drift; (3) rename test_default_timeout_preserved_when_no_config -> test_explicit_global_timeout_propagates_to_general_purpose since it intentionally exercises an explicit non-default 900. No runtime behavior change.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

backend/tests/test_subagent_timeout_config.py

@@ -97,7 +97,7 @@ class TestSubagentOverrideConfig:
 class TestSubagentsAppConfigDefaults:
     def test_default_timeout(self):
         config = SubagentsAppConfig()
-        assert config.timeout_seconds == 900
+        assert config.timeout_seconds == 1800
 
     def test_default_max_turns_override_is_none(self):
         config = SubagentsAppConfig()
@@ -281,7 +281,7 @@ class TestLoadSubagentsConfig:
     def test_load_empty_dict_uses_defaults(self):
         load_subagents_config_from_dict({})
         cfg = get_subagents_app_config()
-        assert cfg.timeout_seconds == 900
+        assert cfg.timeout_seconds == 1800
         assert cfg.max_turns is None
         assert cfg.agents == {}
 
@@ -319,13 +319,30 @@ class TestRegistryGetSubagentConfig:
         assert get_subagent_config("general-purpose") is not None
         assert get_subagent_config("bash") is not None
 
-    def test_default_timeout_preserved_when_no_config(self):
+    def test_explicit_global_timeout_propagates_to_general_purpose(self):
+        """An explicit global timeout (here the non-default 900) propagates to a
+        built-in agent, while max_turns still comes from the builtin def (150).
+        """
         from deerflow.subagents.registry import get_subagent_config
 
         _reset_subagents_config(timeout_seconds=900)
         config = get_subagent_config("general-purpose")
         assert config.timeout_seconds == 900
-        assert config.max_turns == 100
+        assert config.max_turns == 150
+
+    def test_builtin_defaults_have_research_headroom(self):
+        """Out-of-box defaults (no config.yaml subagents section) must give
+        general-purpose enough turns/time for deep research, which previously
+        failed with GraphRecursionError at the old max_turns=100 limit.
+        """
+        from deerflow.subagents.registry import get_subagent_config
+
+        load_subagents_config_from_dict({})  # no subagents config -> model defaults
+        config = get_subagent_config("general-purpose")
+        assert config.max_turns == 150
+        assert config.timeout_seconds == 1800
+        # Pin bash too so the config.example.yaml "bash=60" doc cannot drift.
+        assert get_subagent_config("bash").max_turns == 60
 
     def test_global_timeout_override_applied(self):
         from deerflow.subagents.registry import get_subagent_config