fix subagent max iteration limit

tests/agent/tools/test_subagent_tools.py

@@ -54,11 +54,129 @@ async def test_subagent_exec_tool_receives_allowed_env_keys(tmp_path):
     mgr.runner.run.assert_awaited_once()
 
 
+@pytest.mark.asyncio
+async def test_subagent_uses_configured_max_iterations(tmp_path):
+    """Subagents should honor the configured tool-iteration limit."""
+    from nanobot.agent.subagent import SubagentManager, SubagentStatus
+    from nanobot.bus.queue import MessageBus
+
+    bus = MessageBus()
+    provider = MagicMock()
+    provider.get_default_model.return_value = "test-model"
+    mgr = SubagentManager(
+        provider=provider,
+        workspace=tmp_path,
+        bus=bus,
+        max_tool_result_chars=_MAX_TOOL_RESULT_CHARS,
+        max_iterations=37,
+    )
+    mgr._announce_result = AsyncMock()
+
+    async def fake_run(spec):
+        assert spec.max_iterations == 37
+        return SimpleNamespace(
+            stop_reason="done",
+            final_content="done",
+            error=None,
+            tool_events=[],
+        )
+
+    mgr.runner.run = AsyncMock(side_effect=fake_run)
+
+    status = SubagentStatus(
+        task_id="sub-1", label="label", task_description="do task", started_at=time.monotonic()
+    )
+    await mgr._run_subagent(
+        "sub-1", "do task", "label", {"channel": "test", "chat_id": "c1"}, status
+    )
+
+    mgr.runner.run.assert_awaited_once()
+
+
+def test_subagent_default_max_iterations_matches_agent_defaults(tmp_path):
+    """Direct SubagentManager construction should use the agent default limit."""
+    from nanobot.agent.subagent import SubagentManager
+    from nanobot.bus.queue import MessageBus
+
+    bus = MessageBus()
+    provider = MagicMock()
+    provider.get_default_model.return_value = "test-model"
+
+    mgr = SubagentManager(
+        provider=provider,
+        workspace=tmp_path,
+        bus=bus,
+        max_tool_result_chars=_MAX_TOOL_RESULT_CHARS,
+    )
+
+    assert mgr.max_iterations == AgentDefaults().max_tool_iterations
+
+
+def test_agent_loop_passes_max_iterations_to_subagents(tmp_path):
+    """AgentLoop's configured limit should be shared with spawned subagents."""
+    from nanobot.agent.loop import AgentLoop
+    from nanobot.bus.queue import MessageBus
+
+    bus = MessageBus()
+    provider = MagicMock()
+    provider.get_default_model.return_value = "test-model"
+
+    loop = AgentLoop(
+        bus=bus,
+        provider=provider,
+        workspace=tmp_path,
+        model="test-model",
+        max_iterations=42,
+    )
+
+    assert loop.subagents.max_iterations == 42
+
+
+@pytest.mark.asyncio
+async def test_agent_loop_syncs_updated_max_iterations_before_run(tmp_path):
+    """Runtime max_iterations changes should be reflected before tool execution."""
+    from nanobot.agent.loop import AgentLoop
+    from nanobot.bus.queue import MessageBus
+
+    bus = MessageBus()
+    provider = MagicMock()
+    provider.get_default_model.return_value = "test-model"
+
+    loop = AgentLoop(
+        bus=bus,
+        provider=provider,
+        workspace=tmp_path,
+        model="test-model",
+        max_iterations=42,
+    )
+    loop.tools.get_definitions = MagicMock(return_value=[])
+
+    async def fake_run(spec):
+        assert spec.max_iterations == 55
+        assert loop.subagents.max_iterations == 55
+        return SimpleNamespace(
+            stop_reason="done",
+            final_content="done",
+            error=None,
+            tool_events=[],
+            messages=[],
+            usage={},
+            had_injections=False,
+            tools_used=[],
+        )
+
+    loop.runner.run = AsyncMock(side_effect=fake_run)
+    loop.max_iterations = 55
+
+    await loop._run_agent_loop([])
+
+    loop.runner.run.assert_awaited_once()
+
+
 @pytest.mark.asyncio
 async def test_drain_pending_blocks_while_subagents_running(tmp_path):
     """_drain_pending should block when no messages are available but sub-agents are still running."""
     from nanobot.agent.loop import AgentLoop
-    from nanobot.agent.subagent import SubagentManager
     from nanobot.bus.events import InboundMessage
     from nanobot.bus.queue import MessageBus
     from nanobot.session.manager import Session
@@ -74,8 +192,6 @@ async def test_drain_pending_blocks_while_subagents_running(tmp_path):
     injection_callback = None
 
     # Capture the injection_callback that _run_agent_loop creates
-    original_run = loop.runner.run
-
     async def fake_runner_run(spec):
         nonlocal injection_callback
         injection_callback = spec.injection_callback