diff --git a/reme_ai/core/op/__init__.py b/reme_ai/core/op/__init__.py
index c009e89f..a48bf276 100644
--- a/reme_ai/core/op/__init__.py
+++ b/reme_ai/core/op/__init__.py
@@ -2,12 +2,14 @@
 
 from .base_op import BaseOp
 from .base_ray_op import BaseRayOp
+from .mcp_tool import MCPTool
 from .parallel_op import ParallelOp
 from .sequential_op import SequentialOp
 
 __all__ = [
     "BaseOp",
     "BaseRayOp",
+    "MCPTool",
     "ParallelOp",
     "SequentialOp",
 ]
diff --git a/reme_ai/core/op/base_op.py b/reme_ai/core/op/base_op.py
index 4c82b64c..5cb5a0a2 100644
--- a/reme_ai/core/op/base_op.py
+++ b/reme_ai/core/op/base_op.py
@@ -126,21 +126,6 @@ class BaseOp:
                 }
         return self._tool_call
 
-    def set_tool_call(self, tool_call: ToolCall | dict):
-        """Set the tool call."""
-        if isinstance(tool_call, dict):
-            self._tool_call = ToolCall(**tool_call)
-        elif isinstance(tool_call, ToolCall):
-            self._tool_call = tool_call
-        else:
-            raise ValueError(f"Invalid tool call: {tool_call}")
-
-        self._tool_call.name = self._tool_call.name or self.name
-        if not self._tool_call.output.properties:
-            self._tool_call.output.properties = {
-                f"{self.name}_result": ToolAttr(type="string", description=f"Execution result of {self.name}"),
-            }
-
     @property
     def input_dict(self) -> dict:
         """Extract required and optional inputs from context based on schema."""
@@ -219,6 +204,26 @@ class BaseOp:
         """Get the response object."""
         return self.context.response
 
+    def set_tool_call(self, tool_call: ToolCall | dict):
+        """Set the tool call."""
+        if isinstance(tool_call, dict):
+            self._tool_call = ToolCall(**tool_call)
+        elif isinstance(tool_call, ToolCall):
+            self._tool_call = tool_call
+        else:
+            raise ValueError(f"Invalid tool call: {tool_call}")
+
+        self._tool_call.name = self._tool_call.name or self.name
+        if not self._tool_call.output.properties:
+            self._tool_call.output.properties = {
+                f"{self.name}_result": ToolAttr(type="string", description=f"Execution result of {self.name}"),
+            }
+
+    def set_language(self, language: str):
+        """Set the language."""
+        self.language = language
+        return self
+
     def before_execute_sync(self):
         """Prepare context and validate before sync execution."""
         self.context.apply_mapping(self.input_mapping)
@@ -318,10 +323,12 @@ class BaseOp:
                 assert self.async_mode == op.async_mode, "Async mode mismatch!"
                 op.name = name
                 self.sub_ops.append(op)
+
         elif isinstance(sub_ops, list):
             for op in sub_ops:
                 assert self.async_mode == op.async_mode, "Async mode mismatch!"
                 self.sub_ops.append(op)
+
         else:
             assert self.async_mode == sub_ops.async_mode, "Async mode mismatch!"
             self.sub_ops.append(sub_ops)
diff --git a/reme_ai/tool/mcp_tool.py b/reme_ai/core/op/mcp_tool.py
similarity index 95%
rename from reme_ai/tool/mcp_tool.py
rename to reme_ai/core/op/mcp_tool.py
index f06275b0..57cbcbd4 100644
--- a/reme_ai/tool/mcp_tool.py
+++ b/reme_ai/core/op/mcp_tool.py
@@ -2,10 +2,10 @@
 
 from typing import List
 
-from ..core.context import C
-from ..core.op import BaseOp
-from ..core.schema import ToolCall
-from ..core.utils import MCPClient
+from .base_op import BaseOp
+from ..context import C
+from ..schema import ToolCall
+from ..utils import MCPClient
 
 
 @C.register_op()
diff --git a/reme_ai/mem_agent/base_memory_agent.py b/reme_ai/mem_agent/base_memory_agent.py
new file mode 100644
index 00000000..b7913ed1
--- /dev/null
+++ b/reme_ai/mem_agent/base_memory_agent.py
@@ -0,0 +1,187 @@
+"""Base memory agent for handling memory operations with tool-based reasoning."""
+
+import asyncio
+from abc import ABCMeta
+
+from loguru import logger
+
+from ..core.enumeration import Role, MemoryType
+from ..core.op import BaseOp
+from ..core.schema import Message, ToolCall
+from ..tool.memory import BaseMemoryTool, ThinkTool
+
+
+class BaseMemoryAgent(BaseOp, metaclass=ABCMeta):
+    """Base class for memory agents that perform reasoning and acting with memory tools."""
+
+    memory_type: MemoryType | None = None
+
+    def __init__(
+        self,
+        max_steps: int = 20,
+        tool_call_interval: float = 0,
+        add_think_tool: bool = False,  # only for instruct model
+        tools: list[BaseMemoryTool] | None = None,
+        **kwargs,
+    ):
+        super().__init__(**kwargs)
+        self.max_steps: int = max_steps
+        self.tool_call_interval: float = tool_call_interval
+        self.add_think_tool: bool = add_think_tool
+        assert not self.sub_ops, "sub_ops must be empty, use `tools`~"
+        if tools:
+            self.sub_ops.extend([t.set_language(self.language) for t in tools])
+
+    def _build_tool_call(self) -> ToolCall:
+        return ToolCall(
+            **{
+                "description": self.get_prompt("tool"),
+                "parameters": {
+                    "type": "object",
+                    "properties": {
+                        "query": {
+                            "type": "string",
+                            "description": "query",
+                        },
+                        "messages": {
+                            "type": "array",
+                            "items": {
+                                "type": "object",
+                                "properties": {
+                                    "role": {
+                                        "type": "string",
+                                        "description": "role",
+                                    },
+                                    "content": {
+                                        "type": "string",
+                                        "description": "content",
+                                    },
+                                },
+                                "required": ["role", "content"],
+                            },
+                        },
+                    },
+                    "required": [],
+                },
+            },
+        )
+
+    @property
+    def tools(self) -> list[BaseMemoryTool]:
+        """Returns the list of memory tools available to the agent."""
+        tools: list[BaseMemoryTool] = [o for o in self.sub_ops if isinstance(o, BaseMemoryTool)]
+        if self.add_think_tool:
+            tools.append(ThinkTool(language=self.language))
+        return tools
+
+    @tools.setter
+    def tools(self, tools: list[BaseMemoryTool] | BaseMemoryTool):
+        """Sets the memory tools for the agent."""
+        self.sub_ops = tools
+
+    def get_messages(self) -> list[Message]:
+        """Extracts and returns messages from the context query or messages."""
+        if self.context.get("query"):
+            messages = [Message(role=Role.USER, content=self.context.query)]
+        elif self.context.get("messages"):
+            messages = [Message(**m) if isinstance(m, dict) else m for m in self.context.messages]
+        else:
+            raise ValueError("input must have either `query` or `messages`")
+        return messages
+
+    async def build_messages(self) -> list[Message]:
+        """Builds and returns the initial messages for the agent."""
+        return self.get_messages()
+
+    async def _reasoning_step(self, messages: list[Message], step: int, **kwargs) -> tuple[Message, bool]:
+        assistant_message: Message = await self.llm.chat(
+            messages=messages,
+            tools=[t.tool_call for t in self.tools],
+            **kwargs,
+        )
+        messages.append(assistant_message)
+        logger.info(f"step{step + 1}.assistant={assistant_message.model_dump_json()}")
+        should_act = bool(assistant_message.tool_calls)
+        return assistant_message, should_act
+
+    async def _acting_step(self, assistant_message: Message, step: int, **kwargs) -> list[Message]:
+        if not assistant_message.tool_calls:
+            return []
+
+        tool_list: list[BaseMemoryTool] = []
+        tool_result_messages: list[Message] = []
+        tool_dict = {t.tool_call.name: t for t in self.tools}
+
+        for j, tool_call in enumerate(assistant_message.tool_calls):
+            if tool_call.name not in tool_dict:
+                logger.warning(f"unknown tool_call.name={tool_call.name}")
+                continue
+
+            logger.info(f"step{step + 1}.{j} submit tool_calls={tool_call.name} argument={tool_call.argument_dict}")
+            tool_copy: BaseMemoryTool = tool_dict[tool_call.name].copy()
+            tool_copy.tool_call.id = tool_call.id
+            tool_list.append(tool_copy)
+            kwargs.update(tool_call.argument_dict)
+            self.submit_async_task(tool_copy.call, **kwargs)
+            if self.tool_call_interval > 0:
+                await asyncio.sleep(self.tool_call_interval)
+
+        await self.join_async_tasks()
+
+        for j, op in enumerate(tool_list):
+            tool_result = str(op.output)
+            tool_message = Message(
+                role=Role.TOOL,
+                content=tool_result,
+                tool_call_id=op.tool_call.id,
+            )
+            tool_result_messages.append(tool_message)
+            logger.info(f"step{step + 1}.{j} join tool_result={tool_result[:200]}...\n\n")
+        return tool_result_messages
+
+    async def react(self, messages: list[Message]):
+        """Performs reasoning and acting steps until completion or max steps reached."""
+        success: bool = False
+        for step in range(self.max_steps):
+            assistant_message, should_act = await self._reasoning_step(messages, step)
+
+            if not should_act:
+                success = True
+                break
+
+            tool_result_messages = await self._acting_step(assistant_message, step)
+            messages.extend(tool_result_messages)
+
+        return messages, success
+
+    async def execute(self):
+        messages = await self.build_messages()
+        for i, message in enumerate(messages):
+            logger.info(f"step0.{i} {message.role} {message.name or ''} {message.simple_dump()}")
+
+        messages, success = await self.react(messages)
+        if messages:
+            if success:
+                self.output = messages[-1].content
+            else:
+                self.output = f"react is not complete with content:\n{messages[-1].content}"
+        else:
+            self.output = "empty messages"
+
+        self.context.response.metadata["messages"] = messages
+        self.context.response.metadata["success"] = success
+
+    @property
+    def memory_target(self) -> str:
+        """Returns the target memory identifier from context."""
+        return self.context.get("memory_target", "")
+
+    @property
+    def ref_memory_id(self) -> str:
+        """Returns the reference memory ID from context."""
+        return self.context.get("ref_memory_id", "")
+
+    @property
+    def author(self) -> str:
+        """Returns the LLM model name as the author identifier."""
+        return self.llm.model_name
diff --git a/reme_ai/tool/__init__.py b/reme_ai/tool/__init__.py
index d7d25f85..f1dcedd3 100644
--- a/reme_ai/tool/__init__.py
+++ b/reme_ai/tool/__init__.py
@@ -3,15 +3,9 @@
 from . import execute
 from . import memory
 from . import search
-from .base_memory_tool import BaseMemoryTool
-from .mcp_tool import MCPTool
-from .think_tool import ThinkTool
 
 __all__ = [
     "execute",
     "memory",
     "search",
-    "BaseMemoryTool",
-    "MCPTool",
-    "ThinkTool",
 ]
diff --git a/reme_ai/tool/memory/__init__.py b/reme_ai/tool/memory/__init__.py
index b6dfb163..15392685 100644
--- a/reme_ai/tool/memory/__init__.py
+++ b/reme_ai/tool/memory/__init__.py
@@ -1,11 +1,13 @@
 """Memory tool operations."""
 
+from .base_memory_tool import BaseMemoryTool
 from .history.add_history_memory import AddHistoryMemory
 from .history.read_history_memory import ReadHistoryMemory
 from .identity.read_identity_memory import ReadIdentityMemory
 from .identity.update_identity_memory import UpdateIdentityMemory
 from .meta.add_meta_memory import AddMetaMemory
 from .meta.read_meta_memory import ReadMetaMemory
+from .think_tool import ThinkTool
 from .vector.add_memory import AddMemory
 from .vector.add_summary_memory import AddSummaryMemory
 from .vector.delete_memory import DeleteMemory
@@ -13,12 +15,14 @@ from .vector.update_memory import UpdateMemory
 from .vector.vector_retrieve_memory import VectorRetrieveMemory
 
 __all__ = [
+    "BaseMemoryTool",
     "AddHistoryMemory",
     "ReadHistoryMemory",
     "ReadIdentityMemory",
     "UpdateIdentityMemory",
     "AddMetaMemory",
     "ReadMetaMemory",
+    "ThinkTool",
     "AddMemory",
     "AddSummaryMemory",
     "DeleteMemory",
diff --git a/reme_ai/tool/base_memory_tool.py b/reme_ai/tool/memory/base_memory_tool.py
similarity index 95%
rename from reme_ai/tool/base_memory_tool.py
rename to reme_ai/tool/memory/base_memory_tool.py
index 7ec1a133..f87286a0 100644
--- a/reme_ai/tool/base_memory_tool.py
+++ b/reme_ai/tool/memory/base_memory_tool.py
@@ -3,10 +3,10 @@
 from abc import ABCMeta
 from pathlib import Path
 
-from ..core.enumeration import MemoryType
-from ..core.op import BaseOp
-from ..core.schema import ToolCall, MemoryNode
-from ..core.utils import CacheHandler
+from ...core.enumeration import MemoryType
+from ...core.op import BaseOp
+from ...core.schema import ToolCall, MemoryNode
+from ...core.utils import CacheHandler
 
 
 class BaseMemoryTool(BaseOp, metaclass=ABCMeta):
diff --git a/reme_ai/tool/memory/history/add_history_memory.py b/reme_ai/tool/memory/history/add_history_memory.py
index 85d0928d..125ebe86 100644
--- a/reme_ai/tool/memory/history/add_history_memory.py
+++ b/reme_ai/tool/memory/history/add_history_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 from ....core.enumeration import MemoryType
 from ....core.schema import ToolCall, Message
diff --git a/reme_ai/tool/memory/history/read_history_memory.py b/reme_ai/tool/memory/history/read_history_memory.py
index a4c7a91b..25c71f8d 100644
--- a/reme_ai/tool/memory/history/read_history_memory.py
+++ b/reme_ai/tool/memory/history/read_history_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 from ....core.schema import MemoryNode
 
diff --git a/reme_ai/tool/memory/identity/read_identity_memory.py b/reme_ai/tool/memory/identity/read_identity_memory.py
index 9247ab69..0e1e5df4 100644
--- a/reme_ai/tool/memory/identity/read_identity_memory.py
+++ b/reme_ai/tool/memory/identity/read_identity_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 
 
diff --git a/reme_ai/tool/memory/identity/update_identity_memory.py b/reme_ai/tool/memory/identity/update_identity_memory.py
index ba0e2de7..dec7444b 100644
--- a/reme_ai/tool/memory/identity/update_identity_memory.py
+++ b/reme_ai/tool/memory/identity/update_identity_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 
 
diff --git a/reme_ai/tool/memory/meta/add_meta_memory.py b/reme_ai/tool/memory/meta/add_meta_memory.py
index cc71f640..2de6cc74 100644
--- a/reme_ai/tool/memory/meta/add_meta_memory.py
+++ b/reme_ai/tool/memory/meta/add_meta_memory.py
@@ -4,7 +4,7 @@ import json
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 from ....core.enumeration import MemoryType
 
diff --git a/reme_ai/tool/memory/meta/read_meta_memory.py b/reme_ai/tool/memory/meta/read_meta_memory.py
index 2a69d799..0aee30c8 100644
--- a/reme_ai/tool/memory/meta/read_meta_memory.py
+++ b/reme_ai/tool/memory/meta/read_meta_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 from ....core.enumeration import MemoryType
 
diff --git a/reme_ai/tool/think_tool.py b/reme_ai/tool/memory/think_tool.py
similarity index 90%
rename from reme_ai/tool/think_tool.py
rename to reme_ai/tool/memory/think_tool.py
index 2e83b3ad..3172010e 100644
--- a/reme_ai/tool/think_tool.py
+++ b/reme_ai/tool/memory/think_tool.py
@@ -4,13 +4,13 @@ This module provides a tool that prompts the model for explicit reflection
 before taking actions, helping agents reason about their next steps.
 """
 
-from ..core.context import C
-from ..core.op import BaseOp
-from ..core.schema import ToolCall
+from .base_memory_tool import BaseMemoryTool
+from ...core.context import C
+from ...core.schema import ToolCall
 
 
 @C.register_op()
-class ThinkTool(BaseOp):
+class ThinkTool(BaseMemoryTool):
     """Utility that prompts the model for explicit reflection text.
 
     This tool provides a thinking mechanism for agents to reflect on:
@@ -20,7 +20,7 @@ class ThinkTool(BaseOp):
     """
 
     def __init__(self, add_output_reflection: bool = False, **kwargs):
-        """Initialize the think tool tool.
+        """Initialize the think tool.
 
         Args:
             add_output_reflection: If True, outputs the reflection content;
diff --git a/reme_ai/tool/think_tool.yaml b/reme_ai/tool/memory/think_tool.yaml
similarity index 100%
rename from reme_ai/tool/think_tool.yaml
rename to reme_ai/tool/memory/think_tool.yaml
diff --git a/reme_ai/tool/memory/vector/add_memory.py b/reme_ai/tool/memory/vector/add_memory.py
index 9a27b370..15fc86c4 100644
--- a/reme_ai/tool/memory/vector/add_memory.py
+++ b/reme_ai/tool/memory/vector/add_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 from ....core.schema import MemoryNode
 
diff --git a/reme_ai/tool/memory/vector/delete_memory.py b/reme_ai/tool/memory/vector/delete_memory.py
index 8c747b57..aa529283 100644
--- a/reme_ai/tool/memory/vector/delete_memory.py
+++ b/reme_ai/tool/memory/vector/delete_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 
 
diff --git a/reme_ai/tool/memory/vector/update_memory.py b/reme_ai/tool/memory/vector/update_memory.py
index d427891d..ad7203bd 100644
--- a/reme_ai/tool/memory/vector/update_memory.py
+++ b/reme_ai/tool/memory/vector/update_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 from ....core.schema import MemoryNode
 
diff --git a/reme_ai/tool/memory/vector/vector_retrieve_memory.py b/reme_ai/tool/memory/vector/vector_retrieve_memory.py
index 9e0cc6c7..f6c7c271 100644
--- a/reme_ai/tool/memory/vector/vector_retrieve_memory.py
+++ b/reme_ai/tool/memory/vector/vector_retrieve_memory.py
@@ -2,7 +2,7 @@
 
 from loguru import logger
 
-from ...base_memory_tool import BaseMemoryTool
+from ..base_memory_tool import BaseMemoryTool
 from ....core.context import C
 from ....core.enumeration import MemoryType
 from ....core.schema import MemoryNode, VectorNode