Update app.py

app.py

@@ -1,4 +1,14 @@
-
+# requirements.txt contents:
+"""
+langgraph>=0.0.25
+langchain_openai>=0.0.4
+langchain_community>=0.0.11
+chromadb>=0.4.15
+openai>=1.9.0
+streamlit>=1.29.0
+requests>=2.31.0
+typing-extensions>=4.9.0
+"""
 
 # ------------------------------
 # Imports & Dependencies
@@ -8,7 +18,7 @@ from langchain_community.vectorstores import Chroma
 from langchain_core.messages import HumanMessage, AIMessage, ToolMessage
 from langchain.text_splitter import RecursiveCharacterTextSplitter
 from langgraph.graph import END, StateGraph
-from langgraph.prebuilt import ToolNode  # Corrected import
+from langgraph.prebuilt import ToolNode
 from langgraph.graph.message import add_messages
 from typing_extensions import TypedDict, Annotated
 from typing import Sequence
@@ -18,9 +28,6 @@ import streamlit as st
 import requests
 from langchain.tools.retriever import create_retriever_tool
 
-# Define our own START constant
-START = "START"
-
 # ------------------------------
 # Dummy Data: Research & Development Texts
 # ------------------------------
@@ -259,18 +266,21 @@ def custom_tools_condition(state: AgentState):
     return END
 
 # ------------------------------
-# Workflow Configuration using LangGraph
+# Workflow Configuration using LangGraph (Corrected)
 # ------------------------------
 workflow = StateGraph(AgentState)
 
+# Add nodes
 workflow.add_node("agent", agent)
 retrieve_node = ToolNode(tools)
 workflow.add_node("retrieve", retrieve_node)
 workflow.add_node("rewrite", rewrite)
 workflow.add_node("generate", generate)
 
-workflow.add_edge(START, "agent")
+# Set entry point
+workflow.set_entry_point("agent")
 
+# Define transitions
 workflow.add_conditional_edges(
     "agent",
     custom_tools_condition,
@@ -280,12 +290,24 @@ workflow.add_conditional_edges(
     }
 )
 
-workflow.add_conditional_edges("retrieve", simple_grade_documents)
+workflow.add_conditional_edges(
+    "retrieve",
+    simple_grade_documents,
+    {
+        "generate": "generate",
+        "rewrite": "rewrite"
+    }
+)
+
 workflow.add_edge("generate", END)
 workflow.add_edge("rewrite", "agent")
 
+# Compile the workflow
 app = workflow.compile()
 
+# ------------------------------
+# Processing Function
+# ------------------------------
 def process_question(user_question, app, config):
     """Process user question through the workflow"""
     events = []