diff --git a/aieng-eval-agents/aieng/agent_evals/async_client_manager.py b/aieng-eval-agents/aieng/agent_evals/async_client_manager.py
index a1f36f42..451912f0 100644
--- a/aieng-eval-agents/aieng/agent_evals/async_client_manager.py
+++ b/aieng-eval-agents/aieng/agent_evals/async_client_manager.py
@@ -7,7 +7,6 @@
 import logging
 
 from aieng.agent_evals.configs import Configs
-from aieng.agent_evals.tools import ReadOnlySqlDatabase
 from langfuse import Langfuse
 from openai import AsyncOpenAI
 
@@ -63,8 +62,6 @@ def __init__(self, configs: Configs | None = None) -> None:
         """
         self._configs: Configs | None = configs
         self._openai_client: AsyncOpenAI | None = None
-        self._aml_db: ReadOnlySqlDatabase | None = None
-        self._report_generation_db: ReadOnlySqlDatabase | None = None
         self._langfuse_client: Langfuse | None = None
         self._otel_instrumented: bool = False
         self._initialized: bool = False
@@ -98,46 +95,6 @@ def openai_client(self) -> AsyncOpenAI:
             self._initialized = True
         return self._openai_client
 
-    def report_generation_db(self, agent_name: str = "ReportGenerationAgent") -> ReadOnlySqlDatabase:
-        """Get or create Report Generation database connection.
-
-        Returns
-        -------
-        ReadOnlySqlDatabase
-            The Report Generation database connection instance.
-        """
-        if self._report_generation_db is None:
-            if self.configs.report_generation_db is None:
-                raise ValueError("Report Generation database configuration is missing.")
-
-            self._report_generation_db = ReadOnlySqlDatabase(
-                connection_uri=self.configs.report_generation_db.build_uri(),
-                agent_name=agent_name,
-            )
-            self._initialized = True
-
-        return self._report_generation_db
-
-    def aml_db(self, agent_name: str = "FraudInvestigationAnalyst") -> ReadOnlySqlDatabase:
-        """Get or create AML database connection.
-
-        Returns
-        -------
-        ReadOnlySqlDatabase
-            The Report Generation database connection instance.
-        """
-        if self._aml_db is None:
-            if self.configs.aml_db is None:
-                raise ValueError("AML database configuration is missing.")
-
-            self._aml_db = ReadOnlySqlDatabase(
-                connection_uri=self.configs.aml_db.build_uri(),
-                agent_name=agent_name,
-            )
-            self._initialized = True
-
-        return self._aml_db
-
     @property
     def langfuse_client(self) -> Langfuse:
         """Get or create Langfuse client.
@@ -183,21 +140,13 @@ def otel_instrumented(self, value: bool) -> None:
     async def close(self) -> None:
         """Close all initialized async clients.
 
-        This method closes the OpenAI client, database connections, and Langfuse
-        client if they have been initialized.
+        This method closes the OpenAI client and Langfuse client
+        if they have been initialized.
         """
         if self._openai_client is not None:
             await self._openai_client.close()
             self._openai_client = None
 
-        if self._aml_db is not None:
-            self._aml_db.close()
-            self._aml_db = None
-
-        if self._report_generation_db is not None:
-            self._report_generation_db.close()
-            self._report_generation_db = None
-
         if self._langfuse_client is not None:
             self._langfuse_client.flush()
             self._langfuse_client = None
diff --git a/aieng-eval-agents/aieng/agent_evals/db_manager.py b/aieng-eval-agents/aieng/agent_evals/db_manager.py
new file mode 100644
index 00000000..af3e06b6
--- /dev/null
+++ b/aieng-eval-agents/aieng/agent_evals/db_manager.py
@@ -0,0 +1,137 @@
+"""Database connection manager for Gradio applications.
+
+Provides centralized DB lifecycle management independent of async client handling,
+avoiding circular imports with the tools package.
+"""
+
+import logging
+
+from aieng.agent_evals.configs import Configs
+from aieng.agent_evals.tools.sql_database import ReadOnlySqlDatabase
+
+
+logger = logging.getLogger(__name__)
+
+
+class DbManager:
+    """Manages database connections with lazy initialization.
+
+    Parameters
+    ----------
+    configs : Configs | None, optional
+        Configuration object. If ``None``, created lazily on first access.
+    """
+
+    _singleton_instance: "DbManager | None" = None
+
+    @classmethod
+    def get_instance(cls) -> "DbManager":
+        """Get the singleton instance of the DB manager.
+
+        Returns
+        -------
+        DbManager
+            The singleton instance of the DB manager.
+        """
+        if cls._singleton_instance is None:
+            cls._singleton_instance = DbManager()
+        return cls._singleton_instance
+
+    def __init__(self, configs: Configs | None = None) -> None:
+        self._configs: Configs | None = configs
+        self._aml_db: ReadOnlySqlDatabase | None = None
+        self._report_generation_db: ReadOnlySqlDatabase | None = None
+
+    @property
+    def configs(self) -> Configs:
+        """Get or create configs instance.
+
+        Returns
+        -------
+        Configs
+            The configuration instance.
+        """
+        if self._configs is None:
+            self._configs = Configs()  # type: ignore[call-arg]
+        return self._configs
+
+    @configs.setter
+    def configs(self, value: Configs) -> None:
+        """Set the configs instance.
+
+        Parameters
+        ----------
+        value : Configs
+            The configuration instance to set.
+        """
+        self._configs = value
+
+    def aml_db(self, agent_name: str = "FraudInvestigationAnalyst") -> ReadOnlySqlDatabase:
+        """Get or create the AML database connection.
+
+        Parameters
+        ----------
+        agent_name : str, optional
+            Name of the agent using this connection,
+            by default ``"FraudInvestigationAnalyst"``.
+
+        Returns
+        -------
+        ReadOnlySqlDatabase
+            The AML database connection instance.
+
+        Raises
+        ------
+        ValueError
+            If AML database configuration is missing.
+        """
+        if self._aml_db is None:
+            if self.configs.aml_db is None:
+                raise ValueError("AML database configuration is missing.")
+
+            self._aml_db = ReadOnlySqlDatabase(
+                connection_uri=self.configs.aml_db.build_uri(),
+                agent_name=agent_name,
+            )
+
+        return self._aml_db
+
+    def report_generation_db(self, agent_name: str = "ReportGenerationAgent") -> ReadOnlySqlDatabase:
+        """Get or create the Report Generation database connection.
+
+        Parameters
+        ----------
+        agent_name : str, optional
+            Name of the agent using this connection,
+            by default ``"ReportGenerationAgent"``.
+
+        Returns
+        -------
+        ReadOnlySqlDatabase
+            The Report Generation database connection instance.
+
+        Raises
+        ------
+        ValueError
+            If Report Generation database configuration is missing.
+        """
+        if self._report_generation_db is None:
+            if self.configs.report_generation_db is None:
+                raise ValueError("Report Generation database configuration is missing.")
+
+            self._report_generation_db = ReadOnlySqlDatabase(
+                connection_uri=self.configs.report_generation_db.build_uri(),
+                agent_name=agent_name,
+            )
+
+        return self._report_generation_db
+
+    def close(self) -> None:
+        """Dispose of all database connections."""
+        if self._aml_db is not None:
+            self._aml_db.close()
+            self._aml_db = None
+
+        if self._report_generation_db is not None:
+            self._report_generation_db.close()
+            self._report_generation_db = None
diff --git a/aieng-eval-agents/aieng/agent_evals/report_generation/agent.py b/aieng-eval-agents/aieng/agent_evals/report_generation/agent.py
index 4daf8a1d..5ac660dc 100644
--- a/aieng-eval-agents/aieng/agent_evals/report_generation/agent.py
+++ b/aieng-eval-agents/aieng/agent_evals/report_generation/agent.py
@@ -21,6 +21,7 @@
 from typing import Any
 
 from aieng.agent_evals.async_client_manager import AsyncClientManager
+from aieng.agent_evals.db_manager import DbManager
 from aieng.agent_evals.langfuse import setup_langfuse_tracer
 from aieng.agent_evals.report_generation.file_writer import ReportFileWriter
 from google.adk.agents import Agent
@@ -60,6 +61,7 @@ def get_report_generation_agent(
 
     # Get the client manager singleton instance
     client_manager = AsyncClientManager.get_instance()
+    db_manager = DbManager.get_instance()
     report_file_writer = ReportFileWriter(reports_output_path)
 
     # Define an agent using Google ADK
@@ -68,8 +70,8 @@ def get_report_generation_agent(
         model=client_manager.configs.default_worker_model,
         instruction=instructions,
         tools=[
-            client_manager.report_generation_db().execute,
-            client_manager.report_generation_db().get_schema_info,
+            db_manager.report_generation_db().execute,
+            db_manager.report_generation_db().get_schema_info,
             report_file_writer.write_xlsx,
         ],
     )
diff --git a/aieng-eval-agents/aieng/agent_evals/report_generation/evaluation.py b/aieng-eval-agents/aieng/agent_evals/report_generation/evaluation.py
index 9099170a..20fe60de 100644
--- a/aieng-eval-agents/aieng/agent_evals/report_generation/evaluation.py
+++ b/aieng-eval-agents/aieng/agent_evals/report_generation/evaluation.py
@@ -16,6 +16,7 @@
 from typing import Any
 
 from aieng.agent_evals.async_client_manager import AsyncClientManager
+from aieng.agent_evals.db_manager import DbManager
 from aieng.agent_evals.report_generation.agent import EventParser, EventType, get_report_generation_agent
 from aieng.agent_evals.report_generation.prompts import (
     MAIN_AGENT_INSTRUCTIONS,
@@ -106,6 +107,7 @@ async def evaluate(
 
     try:
         # Gracefully close the services
+        DbManager.get_instance().close()
         await client_manager.close()
     except Exception as e:
         logger.warning(f"Client manager services not closed successfully: {e}")
diff --git a/aieng-eval-agents/tests/aieng/agent_evals/test_async_client_manager.py b/aieng-eval-agents/tests/aieng/agent_evals/test_async_client_manager.py
new file mode 100644
index 00000000..93424e5a
--- /dev/null
+++ b/aieng-eval-agents/tests/aieng/agent_evals/test_async_client_manager.py
@@ -0,0 +1,84 @@
+"""Tests for AsyncClientManager singleton and client lifecycle."""
+
+from unittest.mock import AsyncMock, MagicMock, patch
+
+import pytest
+from aieng.agent_evals.async_client_manager import AsyncClientManager
+
+
+@pytest.fixture(autouse=True)
+def _reset_singleton():
+    """Reset AsyncClientManager singleton before and after each test."""
+    AsyncClientManager._singleton_instance = None
+    yield
+    AsyncClientManager._singleton_instance = None
+
+
+class TestGetInstance:
+    """Tests for the get_instance() class method."""
+
+    def test_returns_same_instance(self):
+        """get_instance() always returns the same object."""
+        first = AsyncClientManager.get_instance()
+        second = AsyncClientManager.get_instance()
+        assert first is second
+
+    def test_constructor_creates_separate_instance(self):
+        """Direct constructor creates a different object than get_instance()."""
+        singleton = AsyncClientManager.get_instance()
+        separate = AsyncClientManager()
+        assert singleton is not separate
+
+
+class TestConfigs:
+    """Tests for lazy config creation."""
+
+    def test_lazy_config_creation(self):
+        """Accessing .configs creates a Configs instance when none was provided."""
+        manager = AsyncClientManager()
+        assert manager._configs is None
+        with patch("aieng.agent_evals.async_client_manager.Configs") as mock_configs_cls:
+            mock_instance = MagicMock()
+            mock_configs_cls.return_value = mock_instance
+            result = manager.configs
+            assert result is mock_instance
+
+
+class TestClose:
+    """Tests for close() method."""
+
+    @pytest.mark.asyncio
+    async def test_closes_openai_client(self):
+        """close() closes the OpenAI client."""
+        manager = AsyncClientManager()
+        mock_client = AsyncMock()
+        manager._openai_client = mock_client
+        manager._initialized = True
+
+        await manager.close()
+
+        mock_client.close.assert_awaited_once()
+        assert manager._openai_client is None
+
+    @pytest.mark.asyncio
+    async def test_flushes_langfuse(self):
+        """close() flushes and clears the Langfuse client."""
+        manager = AsyncClientManager()
+        mock_langfuse = MagicMock()
+        manager._langfuse_client = mock_langfuse
+        manager._initialized = True
+
+        await manager.close()
+
+        mock_langfuse.flush.assert_called_once()
+        assert manager._langfuse_client is None
+
+    @pytest.mark.asyncio
+    async def test_resets_initialized(self):
+        """close() sets _initialized to False."""
+        manager = AsyncClientManager()
+        manager._initialized = True
+
+        await manager.close()
+
+        assert manager._initialized is False
diff --git a/aieng-eval-agents/tests/aieng/agent_evals/test_db_manager.py b/aieng-eval-agents/tests/aieng/agent_evals/test_db_manager.py
new file mode 100644
index 00000000..65387219
--- /dev/null
+++ b/aieng-eval-agents/tests/aieng/agent_evals/test_db_manager.py
@@ -0,0 +1,161 @@
+"""Tests for DbManager singleton and database connection management."""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+from aieng.agent_evals.db_manager import DbManager
+
+
+@pytest.fixture(autouse=True)
+def _reset_singleton():
+    """Reset DbManager singleton before and after each test."""
+    DbManager._singleton_instance = None
+    yield
+    DbManager._singleton_instance = None
+
+
+class TestGetInstance:
+    """Tests for the get_instance() class method."""
+
+    def test_returns_same_instance(self):
+        """get_instance() always returns the same object."""
+        assert DbManager.get_instance() is DbManager.get_instance()
+
+    def test_constructor_creates_separate_instance(self):
+        """Direct constructor creates a different object than get_instance()."""
+        singleton = DbManager.get_instance()
+        separate = DbManager()
+        assert singleton is not separate
+
+
+class TestConfigHandling:
+    """Tests for lazy config creation and setter."""
+
+    def test_lazy_config_creation(self):
+        """Accessing .configs creates a Configs instance when none was provided."""
+        manager = DbManager()
+        assert manager._configs is None
+        with patch("aieng.agent_evals.db_manager.Configs") as mock_configs_cls:
+            mock_instance = MagicMock()
+            mock_configs_cls.return_value = mock_instance
+            result = manager.configs
+            assert result is mock_instance
+
+    def test_configs_setter(self):
+        """Setting .configs stores the value."""
+        manager = DbManager()
+        mock_configs = MagicMock()
+        manager.configs = mock_configs
+        assert manager.configs is mock_configs
+
+
+class TestAmlDb:
+    """Tests for aml_db() method."""
+
+    def test_raises_when_config_missing(self):
+        """aml_db() raises ValueError when aml_db config is None."""
+        mock_configs = MagicMock()
+        mock_configs.aml_db = None
+        manager = DbManager(configs=mock_configs)
+        with pytest.raises(ValueError, match="AML database configuration is missing"):
+            manager.aml_db()
+
+    @patch("aieng.agent_evals.db_manager.ReadOnlySqlDatabase")
+    def test_creates_correct_connection(self, mock_db_cls):
+        """aml_db() creates a ReadOnlySqlDatabase with the right URI."""
+        mock_configs = MagicMock()
+        mock_configs.aml_db.build_uri.return_value = "sqlite:///test.db"
+        manager = DbManager(configs=mock_configs)
+
+        result = manager.aml_db()
+
+        mock_db_cls.assert_called_once_with(
+            connection_uri="sqlite:///test.db",
+            agent_name="FraudInvestigationAnalyst",
+        )
+        assert result is mock_db_cls.return_value
+
+    @patch("aieng.agent_evals.db_manager.ReadOnlySqlDatabase")
+    def test_returns_cached_instance(self, mock_db_cls):
+        """Repeated calls return the same instance without re-creating."""
+        mock_configs = MagicMock()
+        mock_configs.aml_db.build_uri.return_value = "sqlite:///test.db"
+        manager = DbManager(configs=mock_configs)
+
+        first = manager.aml_db()
+        second = manager.aml_db()
+
+        assert first is second
+        assert mock_db_cls.call_count == 1
+
+
+class TestReportGenerationDb:
+    """Tests for report_generation_db() method."""
+
+    def test_raises_when_config_missing(self):
+        """report_generation_db() raises ValueError when config is None."""
+        mock_configs = MagicMock()
+        mock_configs.report_generation_db = None
+        manager = DbManager(configs=mock_configs)
+        with pytest.raises(ValueError, match="Report Generation database configuration is missing"):
+            manager.report_generation_db()
+
+    @patch("aieng.agent_evals.db_manager.ReadOnlySqlDatabase")
+    def test_creates_correct_connection(self, mock_db_cls):
+        """report_generation_db() creates a ReadOnlySqlDatabase with the right URI."""
+        mock_configs = MagicMock()
+        mock_configs.report_generation_db.build_uri.return_value = "sqlite:///reports.db"
+        manager = DbManager(configs=mock_configs)
+
+        result = manager.report_generation_db()
+
+        mock_db_cls.assert_called_once_with(
+            connection_uri="sqlite:///reports.db",
+            agent_name="ReportGenerationAgent",
+        )
+        assert result is mock_db_cls.return_value
+
+    @patch("aieng.agent_evals.db_manager.ReadOnlySqlDatabase")
+    def test_returns_cached_instance(self, mock_db_cls):
+        """Repeated calls return the same instance without re-creating."""
+        mock_configs = MagicMock()
+        mock_configs.report_generation_db.build_uri.return_value = "sqlite:///reports.db"
+        manager = DbManager(configs=mock_configs)
+
+        first = manager.report_generation_db()
+        second = manager.report_generation_db()
+
+        assert first is second
+        assert mock_db_cls.call_count == 1
+
+
+class TestClose:
+    """Tests for close() method."""
+
+    @patch("aieng.agent_evals.db_manager.ReadOnlySqlDatabase")
+    def test_disposes_both_connections(self, mock_db_cls):
+        """close() disposes both DB connections and sets them to None."""
+        mock_aml = MagicMock()
+        mock_report = MagicMock()
+        mock_db_cls.side_effect = [mock_aml, mock_report]
+
+        mock_configs = MagicMock()
+        mock_configs.aml_db.build_uri.return_value = "sqlite:///aml.db"
+        mock_configs.report_generation_db.build_uri.return_value = "sqlite:///reports.db"
+        manager = DbManager(configs=mock_configs)
+
+        manager.aml_db()
+        manager.report_generation_db()
+
+        manager.close()
+
+        mock_aml.close.assert_called_once()
+        mock_report.close.assert_called_once()
+        assert manager._aml_db is None
+        assert manager._report_generation_db is None
+
+    def test_idempotent_when_no_connections(self):
+        """close() is a no-op when no connections have been created."""
+        mock_configs = MagicMock()
+        manager = DbManager(configs=mock_configs)
+        manager.close()  # Should not raise
diff --git a/implementations/aml_investigation/agent.py b/implementations/aml_investigation/agent.py
index f3a2b6e3..0a4e01bb 100644
--- a/implementations/aml_investigation/agent.py
+++ b/implementations/aml_investigation/agent.py
@@ -19,8 +19,8 @@
 
 import google.genai.types
 from aieng.agent_evals.aml_investigation.data import AnalystOutput, CaseRecord
-from aieng.agent_evals.async_client_manager import AsyncClientManager
 from aieng.agent_evals.async_utils import rate_limited
+from aieng.agent_evals.db_manager import DbManager
 from aieng.agent_evals.tools import ReadOnlySqlDatabase
 from dotenv import load_dotenv
 from google.adk.agents import Agent
@@ -94,15 +94,13 @@
 @lru_cache(maxsize=1)
 def _get_db() -> ReadOnlySqlDatabase:
     """Lazily construct the read-only database tool from environment configuration."""
-    client_manager = AsyncClientManager().get_instance()
-    return client_manager.aml_db()
+    return DbManager.get_instance().aml_db()
 
 
-async def _try_close_db() -> None:
+def _try_close_db() -> None:
     """Close the lazily initialized database tool if it was created."""
     if _get_db.cache_info().currsize:
-        client_manager = AsyncClientManager().get_instance()
-        await client_manager.close()
+        DbManager.get_instance().close()
         _get_db.cache_clear()
 
 
@@ -289,7 +287,7 @@ async def _main() -> None:
             logger.info("  TP=%d  FP=%d", tp, fp)
             logger.info("  FN=%d  TN=%d", fn, tn)
     finally:
-        await _try_close_db()
+        _try_close_db()
 
 
 if __name__ == "__main__":
diff --git a/implementations/report_generation/data/import_online_retail_data.py b/implementations/report_generation/data/import_online_retail_data.py
index 79a2c835..baee0a90 100644
--- a/implementations/report_generation/data/import_online_retail_data.py
+++ b/implementations/report_generation/data/import_online_retail_data.py
@@ -35,7 +35,7 @@ def main(dataset_path: str):
     dataset_path : str
         The path to the CSV file containing the dataset.
     """
-    client_manager = AsyncClientManager().get_instance()
+    client_manager = AsyncClientManager.get_instance()
 
     assert client_manager.configs.report_generation_db, "Report generation database configuration is missing"
     assert client_manager.configs.report_generation_db.database, "Report generation database path is missing"
diff --git a/implementations/report_generation/demo.py b/implementations/report_generation/demo.py
index 7771b9b7..a2ef39a4 100644
--- a/implementations/report_generation/demo.py
+++ b/implementations/report_generation/demo.py
@@ -14,6 +14,7 @@
 import click
 import gradio as gr
 from aieng.agent_evals.async_client_manager import AsyncClientManager
+from aieng.agent_evals.db_manager import DbManager
 from aieng.agent_evals.report_generation.agent import get_report_generation_agent
 from aieng.agent_evals.report_generation.prompts import MAIN_AGENT_INSTRUCTIONS
 from dotenv import load_dotenv
@@ -144,6 +145,7 @@ def start_gradio_app(enable_trace: bool = True, enable_public_link: bool = False
             allowed_paths=[str(get_reports_output_path().absolute())],
         )
     finally:
+        DbManager.get_instance().close()
         asyncio.run(AsyncClientManager.get_instance().close())