diff --git a/knowledgehub/loaders/__init__.py b/knowledgehub/loaders/__init__.py
index a1d812a..281ea75 100644
--- a/knowledgehub/loaders/__init__.py
+++ b/knowledgehub/loaders/__init__.py
@@ -1,6 +1,12 @@
-from .base import AutoReader
+from .base import AutoReader, DirectoryReader
 from .excel_loader import PandasExcelReader
 from .mathpix_loader import MathpixPDFReader
 from .ocr_loader import OCRReader
 
-__all__ = ["AutoReader", "PandasExcelReader", "MathpixPDFReader", "OCRReader"]
+__all__ = [
+    "AutoReader",
+    "PandasExcelReader",
+    "MathpixPDFReader",
+    "OCRReader",
+    "DirectoryReader",
+]
diff --git a/knowledgehub/loaders/base.py b/knowledgehub/loaders/base.py
index 804e765..70fead7 100644
--- a/knowledgehub/loaders/base.py
+++ b/knowledgehub/loaders/base.py
@@ -1,13 +1,14 @@
 from pathlib import Path
 from typing import Any, List, Type, Union
 
-from llama_index import download_loader
+from llama_index import SimpleDirectoryReader, download_loader
 from llama_index.readers.base import BaseReader
 
+from ..base import BaseComponent
 from ..documents.base import Document
 
 
-class AutoReader(BaseReader):
+class AutoReader(BaseComponent, BaseReader):
     """General auto reader for a variety of files. (based on llama-hub)"""
 
     def __init__(self, reader_type: Union[str, Type[BaseReader]]) -> None:
@@ -17,6 +18,7 @@ class AutoReader(BaseReader):
             self._reader = download_loader(reader_type)()
         else:
             self._reader = reader_type()
+        super().__init__()
 
     def load_data(self, file: Union[Path, str], **kwargs: Any) -> List[Document]:
         documents = self._reader.load_data(file=file, **kwargs)
@@ -24,3 +26,42 @@ class AutoReader(BaseReader):
         # convert Document to new base class from kotaemon
         converted_documents = [Document.from_dict(doc.to_dict()) for doc in documents]
         return converted_documents
+
+    def run(self, file: Union[Path, str], **kwargs: Any) -> List[Document]:
+        return self.load_data(file=file, **kwargs)
+
+
+class LIBaseReader(BaseComponent, BaseReader):
+    _reader_class: Type[BaseReader]
+
+    def __init__(self, *args, **kwargs):
+        if self._reader_class is None:
+            raise AttributeError(
+                "Require `_reader_class` to set a BaseReader class from LlamarIndex"
+            )
+
+        self._reader = self._reader_class(*args, **kwargs)
+        super().__init__()
+
+    def __setattr__(self, name: str, value: Any) -> None:
+        if name.startswith("_"):
+            return super().__setattr__(name, value)
+
+        return setattr(self._reader, name, value)
+
+    def __getattr__(self, name: str) -> Any:
+        return getattr(self._reader, name)
+
+    def load_data(self, *args, **kwargs: Any) -> List[Document]:
+        documents = self._reader.load_data(*args, **kwargs)
+
+        # convert Document to new base class from kotaemon
+        converted_documents = [Document.from_dict(doc.to_dict()) for doc in documents]
+        return converted_documents
+
+    def run(self, *args, **kwargs: Any) -> List[Document]:
+        return self.load_data(*args, **kwargs)
+
+
+class DirectoryReader(LIBaseReader):
+    _reader_class = SimpleDirectoryReader
diff --git a/knowledgehub/parsers/__init__.py b/knowledgehub/parsers/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/knowledgehub/parsers/splitter.py b/knowledgehub/parsers/splitter.py
new file mode 100644
index 0000000..c9b1203
--- /dev/null
+++ b/knowledgehub/parsers/splitter.py
@@ -0,0 +1,65 @@
+from typing import Any, List, Sequence, Type
+
+from llama_index.node_parser import SimpleNodeParser as LISimpleNodeParser
+from llama_index.node_parser.interface import NodeParser
+from llama_index.text_splitter import TokenTextSplitter
+
+from kotaemon.base import BaseComponent
+
+from ..documents.base import Document
+
+__all__ = ["TokenTextSplitter"]
+
+
+class LINodeParser(BaseComponent):
+    _parser_class: Type[NodeParser]
+
+    def __init__(self, *args, **kwargs):
+        if self._parser_class is None:
+            raise AttributeError(
+                "Require `_parser_class` to set a NodeParser class from LlamarIndex"
+            )
+        self._parser = self._parser_class(*args, **kwargs)
+        super().__init__()
+
+    def __setattr__(self, name: str, value: Any) -> None:
+        if name.startswith("_") or name in self._protected_keywords():
+            return super().__setattr__(name, value)
+
+        return setattr(self._parser, name, value)
+
+    def __getattr__(self, name: str) -> Any:
+        return getattr(self._parser, name)
+
+    def get_nodes_from_documents(
+        self,
+        documents: Sequence[Document],
+        show_progress: bool = False,
+    ) -> List[Document]:
+        documents = self._parser.get_nodes_from_documents(
+            documents=documents, show_progress=show_progress
+        )
+        # convert Document to new base class from kotaemon
+        converted_documents = [Document.from_dict(doc.to_dict()) for doc in documents]
+        return converted_documents
+
+    def run(
+        self,
+        documents: Sequence[Document],
+        show_progress: bool = False,
+    ) -> List[Document]:
+        return self.get_nodes_from_documents(
+            documents=documents, show_progress=show_progress
+        )
+
+
+class SimpleNodeParser(LINodeParser):
+    _parser_class = LISimpleNodeParser
+
+    def __init__(self, *args, **kwargs):
+        chunk_size = kwargs.pop("chunk_size", 512)
+        chunk_overlap = kwargs.pop("chunk_overlap", 0)
+        kwargs["text_splitter"] = TokenTextSplitter(
+            chunk_size=chunk_size, chunk_overlap=chunk_overlap
+        )
+        super().__init__(*args, **kwargs)
diff --git a/knowledgehub/pipelines/agents/__init__.py b/knowledgehub/pipelines/agents/__init__.py
index 3a12096..a9caa08 100644
--- a/knowledgehub/pipelines/agents/__init__.py
+++ b/knowledgehub/pipelines/agents/__init__.py
@@ -1,3 +1,5 @@
 from .base import BaseAgent
+from .react.agent import ReactAgent
+from .rewoo.agent import RewooAgent
 
-__all__ = ["BaseAgent"]
+__all__ = ["BaseAgent", "ReactAgent", "RewooAgent"]
diff --git a/knowledgehub/pipelines/indexing.py b/knowledgehub/pipelines/indexing.py
index 1935268..fe69667 100644
--- a/knowledgehub/pipelines/indexing.py
+++ b/knowledgehub/pipelines/indexing.py
@@ -1,5 +1,6 @@
 import uuid
-from typing import List, Optional
+from pathlib import Path
+from typing import List, Union
 
 from theflow import Node, Param
 
@@ -9,6 +10,9 @@ from ..documents.base import Document
 from ..embeddings import BaseEmbeddings
 from ..vectorstores import BaseVectorStore
 
+VECTOR_STORE_FNAME = "vectorstore"
+DOC_STORE_FNAME = "docstore"
+
 
 class IndexVectorStoreFromDocumentPipeline(BaseComponent):
     """Ingest the document, run through the embedding, and store the embedding in a
@@ -20,7 +24,7 @@ class IndexVectorStoreFromDocumentPipeline(BaseComponent):
     """
 
     vector_store: Param[BaseVectorStore] = Param()
-    doc_store: Optional[BaseDocumentStore] = None
+    doc_store: Param[BaseDocumentStore] = Param()
     embedding: Node[BaseEmbeddings] = Node()
 
     # TODO: refer to llama_index's storage as well
@@ -30,7 +34,7 @@ class IndexVectorStoreFromDocumentPipeline(BaseComponent):
         self.run_batch_document([document])
 
     def run_batch_raw(self, text: List[str]) -> None:
-        documents = [Document(t, id_=str(uuid.uuid4())) for t in text]
+        documents = [Document(text=t, id_=str(uuid.uuid4())) for t in text]
         self.run_batch_document(documents)
 
     def run_document(self, text: Document) -> None:
@@ -57,13 +61,31 @@ class IndexVectorStoreFromDocumentPipeline(BaseComponent):
             return True
         return False
 
-    def persist(self, path: str):
+    def save(
+        self,
+        path: Union[str, Path],
+        vectorstore_fname: str = VECTOR_STORE_FNAME,
+        docstore_fname: str = DOC_STORE_FNAME,
+    ):
         """Save the whole state of the indexing pipeline vector store and all
         necessary information to disk
 
         Args:
             path (str): path to save the state
         """
+        if isinstance(path, str):
+            path = Path(path)
+        self.vector_store.save(path / vectorstore_fname)
+        self.doc_store.save(path / docstore_fname)
 
-    def load(self, path: str):
+    def load(
+        self,
+        path: Union[str, Path],
+        vectorstore_fname: str = VECTOR_STORE_FNAME,
+        docstore_fname: str = DOC_STORE_FNAME,
+    ):
         """Load all information from disk to an object"""
+        if isinstance(path, str):
+            path = Path(path)
+        self.vector_store.load(path / vectorstore_fname)
+        self.doc_store.load(path / docstore_fname)
diff --git a/knowledgehub/pipelines/retrieving.py b/knowledgehub/pipelines/retrieving.py
index 64d4e6b..eb6656b 100644
--- a/knowledgehub/pipelines/retrieving.py
+++ b/knowledgehub/pipelines/retrieving.py
@@ -1,5 +1,6 @@
 from abc import abstractmethod
-from typing import List, Optional
+from pathlib import Path
+from typing import List, Union
 
 from theflow import Node, Param
 
@@ -9,6 +10,9 @@ from ..documents.base import Document, RetrievedDocument
 from ..embeddings import BaseEmbeddings
 from ..vectorstores import BaseVectorStore
 
+VECTOR_STORE_FNAME = "vectorstore"
+DOC_STORE_FNAME = "docstore"
+
 
 class BaseRetrieval(BaseComponent):
     """Define the base interface of a retrieval pipeline"""
@@ -38,7 +42,7 @@ class RetrieveDocumentFromVectorStorePipeline(BaseRetrieval):
     """Retrieve list of documents from vector store"""
 
     vector_store: Param[BaseVectorStore] = Param()
-    doc_store: Optional[BaseDocumentStore] = None
+    doc_store: Param[BaseDocumentStore] = Param()
     embedding: Node[BaseEmbeddings] = Node()
     # TODO: refer to llama_index's storage as well
 
@@ -86,13 +90,31 @@ class RetrieveDocumentFromVectorStorePipeline(BaseRetrieval):
             return True
         return False
 
-    def persist(self, path: str):
+    def save(
+        self,
+        path: Union[str, Path],
+        vectorstore_fname: str = VECTOR_STORE_FNAME,
+        docstore_fname: str = DOC_STORE_FNAME,
+    ):
         """Save the whole state of the indexing pipeline vector store and all
         necessary information to disk
 
         Args:
             path (str): path to save the state
         """
+        if isinstance(path, str):
+            path = Path(path)
+        self.vector_store.save(path / vectorstore_fname)
+        self.doc_store.save(path / docstore_fname)
 
-    def load(self, path: str):
+    def load(
+        self,
+        path: Union[str, Path],
+        vectorstore_fname: str = VECTOR_STORE_FNAME,
+        docstore_fname: str = DOC_STORE_FNAME,
+    ):
         """Load all information from disk to an object"""
+        if isinstance(path, str):
+            path = Path(path)
+        self.vector_store.load(path / vectorstore_fname)
+        self.doc_store.load(path / docstore_fname)
diff --git a/knowledgehub/pipelines/tools/base.py b/knowledgehub/pipelines/tools/base.py
index 4e95ddb..fb5688e 100644
--- a/knowledgehub/pipelines/tools/base.py
+++ b/knowledgehub/pipelines/tools/base.py
@@ -1,6 +1,7 @@
 from abc import abstractmethod
 from typing import Any, Callable, Dict, Optional, Tuple, Type, Union
 
+from langchain.agents import Tool as LCTool
 from pydantic import BaseModel
 
 from kotaemon.base import BaseComponent
@@ -87,6 +88,10 @@ class BaseTool(BaseComponent):
             )
         return observation
 
+    def to_langchain_format(self) -> LCTool:
+        """Convert this tool to Langchain format to use with its agent"""
+        return LCTool(name=self.name, description=self.description, func=self.run)
+
     def run_raw(
         self,
         tool_input: Union[str, Dict],
@@ -122,6 +127,15 @@ class BaseTool(BaseComponent):
         """Tool does not support processing batch"""
         return False
 
+    @classmethod
+    def from_langchain_format(cls, langchain_tool: LCTool) -> "BaseTool":
+        """Wrapper for Langchain Tool"""
+        new_tool = BaseTool(
+            name=langchain_tool.name, description=langchain_tool.description
+        )
+        new_tool._run_tool = langchain_tool._run  # type: ignore
+        return new_tool
+
 
 class ComponentTool(BaseTool):
     """
@@ -130,6 +144,11 @@ class ComponentTool(BaseTool):
     """
 
     component: BaseComponent
+    postprocessor: Optional[Callable] = None
 
     def _run_tool(self, *args: Any, **kwargs: Any) -> Any:
-        return self.component(*args, **kwargs)
+        output = self.component(*args, **kwargs)
+        if self.postprocessor:
+            output = self.postprocessor(output)
+
+        return output
diff --git a/knowledgehub/vectorstores/chroma.py b/knowledgehub/vectorstores/chroma.py
index 8c55a4f..462a89d 100644
--- a/knowledgehub/vectorstores/chroma.py
+++ b/knowledgehub/vectorstores/chroma.py
@@ -67,6 +67,9 @@ class ChromaVectorStore(LlamaIndexVectorStore):
             collection_name = self._client.client.name
         self._client.client._client.delete_collection(collection_name)
 
+    def count(self) -> int:
+        return self._collection.count()
+
     def save(self, *args, **kwargs):
         pass
 
diff --git a/knowledgehub/vectorstores/in_memory.py b/knowledgehub/vectorstores/in_memory.py
index 86e82d2..4bd8a5f 100644
--- a/knowledgehub/vectorstores/in_memory.py
+++ b/knowledgehub/vectorstores/in_memory.py
@@ -44,9 +44,7 @@ class InMemoryVectorStore(LlamaIndexVectorStore):
         """
         self._client.persist(persist_path=save_path, fs=fs)
 
-    def load(
-        self, load_path: str, fs: Optional[fsspec.AbstractFileSystem] = None
-    ) -> "InMemoryVectorStore":
+    def load(self, load_path: str, fs: Optional[fsspec.AbstractFileSystem] = None):
 
         """Create a SimpleKVStore from a load directory.
 
@@ -54,4 +52,4 @@ class InMemoryVectorStore(LlamaIndexVectorStore):
             load_path: Path of loading vector.
             fs: An abstract super-class for pythonic file-systems
         """
-        return self._client.from_persist_path(persist_path=load_path, fs=fs)
+        self._client = self._client.from_persist_path(persist_path=load_path, fs=fs)
diff --git a/setup.py b/setup.py
index 065d344..003bf75 100644
--- a/setup.py
+++ b/setup.py
@@ -53,6 +53,7 @@ setuptools.setup(
             "openai",
             "chromadb",
             "wikipedia",
+            "duckduckgo-search",
             "googlesearch-python",
             "python-dotenv",
             "pytest-mock",
diff --git a/tests/test_agent.py b/tests/test_agent.py
index e646b6e..f2d1535 100644
--- a/tests/test_agent.py
+++ b/tests/test_agent.py
@@ -1,11 +1,19 @@
 from unittest.mock import patch
 
+import pytest
+
 from kotaemon.llms.chats.openai import AzureChatOpenAI
 from kotaemon.pipelines.agents.react import ReactAgent
 from kotaemon.pipelines.agents.rewoo import RewooAgent
-from kotaemon.pipelines.tools import GoogleSearchTool, LLMTool, WikipediaTool
+from kotaemon.pipelines.tools import (
+    BaseTool,
+    GoogleSearchTool,
+    LLMTool,
+    WikipediaTool,
+)
 
 FINAL_RESPONSE_TEXT = "Hello Cinnamon AI!"
+
 _openai_chat_completion_responses_rewoo = [
     {
         "id": "chatcmpl-7qyuw6Q1CFCpcKsMdFkmUPUa7JP2x",
@@ -73,19 +81,61 @@ _openai_chat_completion_responses_react = [
     ]
 ]
 
+_openai_chat_completion_responses_react_langchain_tool = [
+    {
+        "id": "chatcmpl-7qyuw6Q1CFCpcKsMdFkmUPUa7JP2x",
+        "object": "chat.completion",
+        "created": 1692338378,
+        "model": "gpt-35-turbo",
+        "choices": [
+            {
+                "index": 0,
+                "finish_reason": "stop",
+                "message": {
+                    "role": "assistant",
+                    "content": text,
+                },
+            }
+        ],
+        "usage": {"completion_tokens": 9, "prompt_tokens": 10, "total_tokens": 19},
+    }
+    for text in [
+        (
+            "I don't have prior knowledge about Cinnamon AI company, "
+            "so I should gather information about it.\n"
+            "Action: Wikipedia\n"
+            "Action Input: Cinnamon AI company\n"
+        ),
+        (
+            "The information retrieved from Wikipedia is not "
+            "about Cinnamon AI company, but about Blue Prism, "
+            "a British multinational software corporation. "
+            "I need to try another source to gather information "
+            "about Cinnamon AI company.\n"
+            "Action: duckduckgo_search\n"
+            "Action Input: Cinnamon AI company\n"
+        ),
+        FINAL_RESPONSE_TEXT,
+    ]
+]
 
-@patch(
-    "openai.api_resources.chat_completion.ChatCompletion.create",
-    side_effect=_openai_chat_completion_responses_rewoo,
-)
-def test_rewoo_agent(openai_completion):
-    llm = AzureChatOpenAI(
+
+@pytest.fixture
+def llm():
+    return AzureChatOpenAI(
         openai_api_base="https://dummy.openai.azure.com/",
         openai_api_key="dummy",
         openai_api_version="2023-03-15-preview",
         deployment_name="dummy-q2",
         temperature=0,
     )
+
+
+@patch(
+    "openai.api_resources.chat_completion.ChatCompletion.create",
+    side_effect=_openai_chat_completion_responses_rewoo,
+)
+def test_rewoo_agent(openai_completion, llm):
     plugins = [
         GoogleSearchTool(),
         WikipediaTool(),
@@ -103,14 +153,7 @@ def test_rewoo_agent(openai_completion):
     "openai.api_resources.chat_completion.ChatCompletion.create",
     side_effect=_openai_chat_completion_responses_react,
 )
-def test_react_agent(openai_completion):
-    llm = AzureChatOpenAI(
-        openai_api_base="https://dummy.openai.azure.com/",
-        openai_api_key="dummy",
-        openai_api_version="2023-03-15-preview",
-        deployment_name="dummy-q2",
-        temperature=0,
-    )
+def test_react_agent(openai_completion, llm):
     plugins = [
         GoogleSearchTool(),
         WikipediaTool(),
@@ -121,3 +164,47 @@ def test_react_agent(openai_completion):
     response = agent("Tell me about Cinnamon AI company")
     openai_completion.assert_called()
     assert response.output == FINAL_RESPONSE_TEXT
+
+
+@patch(
+    "openai.api_resources.chat_completion.ChatCompletion.create",
+    side_effect=_openai_chat_completion_responses_react,
+)
+def test_react_agent_langchain(openai_completion, llm):
+    from langchain.agents import AgentType, initialize_agent
+
+    plugins = [
+        GoogleSearchTool(),
+        WikipediaTool(),
+        LLMTool(llm=llm),
+    ]
+    langchain_plugins = [tool.to_langchain_format() for tool in plugins]
+    agent = initialize_agent(
+        langchain_plugins,
+        llm.agent,
+        agent=AgentType.OPENAI_FUNCTIONS,
+        verbose=True,
+    )
+    response = agent("Tell me about Cinnamon AI company")
+    openai_completion.assert_called()
+    assert response
+
+
+@patch(
+    "openai.api_resources.chat_completion.ChatCompletion.create",
+    side_effect=_openai_chat_completion_responses_react_langchain_tool,
+)
+def test_react_agent_with_langchain_tools(openai_completion, llm):
+    from langchain.tools import DuckDuckGoSearchRun, WikipediaQueryRun
+    from langchain.utilities import WikipediaAPIWrapper
+
+    wikipedia = WikipediaQueryRun(api_wrapper=WikipediaAPIWrapper())
+    search = DuckDuckGoSearchRun()
+
+    langchain_plugins = [wikipedia, search]
+    plugins = [BaseTool.from_langchain_format(tool) for tool in langchain_plugins]
+    agent = ReactAgent(llm=llm, plugins=plugins, max_iterations=4)
+
+    response = agent("Tell me about Cinnamon AI company")
+    openai_completion.assert_called()
+    assert response.output == FINAL_RESPONSE_TEXT
diff --git a/tests/test_vectorstore.py b/tests/test_vectorstore.py
index 553acea..89fc3b2 100644
--- a/tests/test_vectorstore.py
+++ b/tests/test_vectorstore.py
@@ -116,8 +116,8 @@ class TestInMemoryVectorStore:
             "3" not in data["text_id_to_ref_doc_id"]
         ), "delete function does not delete data completely"
         db2 = InMemoryVectorStore()
-        output = db2.load(load_path=tmp_path / "test_save_load_delete.json")
-        assert output.get("2") == [
+        db2.load(load_path=tmp_path / "test_save_load_delete.json")
+        assert db2.get("2") == [
             0.4,
             0.5,
             0.6,