fix:env AGENT_RECURSION_LIMIT not work (#453)

* fix:env AGENT_RECURSION_LIMIT not work

* fix:add test

* black tests/unit/config/test_configuration.py

---------

Co-authored-by: Willem Jiang <willem.jiang@gmail.com>

tests/unit/config/test_configuration.py

@@ -88,3 +88,49 @@ def test_from_runnable_config_with_no_config():
     assert config.max_search_results == 3
     assert config.resources == []
     assert config.mcp_settings is None
+
+
+def test_get_recursion_limit_default():
+    from src.config.configuration import get_recursion_limit
+
+    result = get_recursion_limit()
+    assert result == 25
+
+
+def test_get_recursion_limit_custom_default():
+    from src.config.configuration import get_recursion_limit
+
+    result = get_recursion_limit(50)
+    assert result == 50
+
+
+def test_get_recursion_limit_from_env(monkeypatch):
+    from src.config.configuration import get_recursion_limit
+
+    monkeypatch.setenv("AGENT_RECURSION_LIMIT", "100")
+    result = get_recursion_limit()
+    assert result == 100
+
+
+def test_get_recursion_limit_invalid_env_value(monkeypatch):
+    from src.config.configuration import get_recursion_limit
+
+    monkeypatch.setenv("AGENT_RECURSION_LIMIT", "invalid")
+    result = get_recursion_limit()
+    assert result == 25
+
+
+def test_get_recursion_limit_negative_env_value(monkeypatch):
+    from src.config.configuration import get_recursion_limit
+
+    monkeypatch.setenv("AGENT_RECURSION_LIMIT", "-5")
+    result = get_recursion_limit()
+    assert result == 25
+
+
+def test_get_recursion_limit_zero_env_value(monkeypatch):
+    from src.config.configuration import get_recursion_limit
+
+    monkeypatch.setenv("AGENT_RECURSION_LIMIT", "0")
+    result = get_recursion_limit()
+    assert result == 25