add services in backend API folder

.gitignore

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+venv/

backend/api/main.py

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+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+app = FastAPI()
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+@app.get("/health")
+def health():
+    return {"status": "ok", "version": "1.0.0"}

backend/api/services/intent_classifier.py

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+class IntentClassifier:
+    def __init__(self):
+        self.rag_keywords = [
+            "internal", "document", "policy", "report", "knowledge",
+            "tenant", "kb", "file", "pdf", "doc", "summarize"
+        ]
+
+        self.web_keywords = [
+            "news", "latest", "search", "google", "web",
+            "internet", "what is happening", "external"
+        ]
+
+        self.admin_keywords = [ 
+            "delete", "remove", "salary", "confidential",
+            "admin", "shutdown", "disable", "breach"
+        ]
+
+    def classify(self, message: str) -> str:
+        if any(keyword in message.lower() for keyword in self.rag_keywords):
+            return "rag"
+        elif any(keyword in message.lower() for keyword in self.web_keywords):
+            return "web"
+        elif any(keyword in message.lower() for keyword in self.admin_keywords):
+            return "admin"
+        else:
+            return "general"

backend/api/services/llm_client.py

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+import requests
+
+class LLMClient:
+    """
+    Uses a LOCAL Llama model via Ollama.
+    """
+
+    def __init__(self, model="llama3"):
+        self.model = model
+        self.url = "http://localhost:11434/api/generate"
+
+    def generate(self, prompt: str) -> str:
+        payload = {
+            "model": self.model,
+            "prompt": prompt,
+            "stream": False
+        }
+
+        try:
+            response = requests.post(self.url, json=payload)
+            data = response.json()
+            return data.get("response", "")
+
+        except Exception as e:
+            return f"⚠️ LOCAL LLM ERROR: {str(e)}"

backend/api/services/prompt_builder.py

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+class PromptBuilder:
+    """
+    Builds the final prompt sent to the LLM.
+    """
+
+    def __init__(self):
+        pass
+
+    def build(
+        self,
+        user_message: str,
+        tool: str,
+        rag_results: list[str] = None,
+        web_results: list[dict] = None,
+        redflag_info: dict = None,
+        tenant_id: str = None
+    ) -> str:
+
+        # 1. Base system prompt
+        system_prompt = (
+            "You are VariaAI, an enterprise-grade MCP agent. "
+            "Always follow tenant isolation: only use data belonging to the tenant. "
+            "Be concise, correct, and safe.\n\n"
+        )
+
+        # 2. Insert admin red-flag context (if triggered)
+        if tool == "admin":
+            system_prompt += (
+                "⚠️ SECURITY NOTICE:\n"
+                "The user request appears sensitive or unsafe.\n"
+                "Provide a safe response, avoid executing harmful instructions.\n\n"
+            )
+
+        # 3. Insert RAG context
+        if tool == "rag" and rag_results:
+            system_prompt += "📄 Relevant Knowledge Base Documents:\n"
+            for i, chunk in enumerate(rag_results, start=1):
+                system_prompt += f"({i}) {chunk}\n"
+            system_prompt += "\n"
+
+        # 4. Insert Web Search results
+        if tool == "web" and web_results:
+            system_prompt += "🌐 Web Search Results:\n"
+            for i, item in enumerate(web_results, start=1):
+                title = item.get("title")
+                snippet = item.get("snippet")
+                system_prompt += f"({i}) {title}\n  {snippet}\n"
+            system_prompt += "\n"
+
+        # 5. Add tenant metadata (optional)
+        if tenant_id:
+            system_prompt += f"Tenant ID: {tenant_id}\n\n"
+
+        # 6. Insert user query
+        system_prompt += "🗣️ User Message:\n"
+        system_prompt += user_message + "\n\n"
+
+        # 7. Instructions for the model
+        system_prompt += (
+            "🎯 Your Task:\n"
+            "- Answer using the context above.\n"
+            "- If context is missing, say so.\n"
+            "- Do not hallucinate facts.\n"
+        )
+
+        return system_prompt

backend/api/services/redflag_detector.py

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+import re
+
+class RedFlagDetector:
+    def __init__(self):
+        # Built-in system red flags
+        self.core_flags = [
+            "delete all data",
+            "wipe database",
+            "salary",
+            "confidential",
+            "password",
+            "secret",
+            "credential",
+            "token",
+            "ssh key",
+            "api key"
+        ]
+
+        # Regex patterns for sensitive info
+        self.regex_patterns = {
+            "email": r"[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-z]{2,}",
+            "credit_card": r"\b(?:\d[ -]*?){13,16}\b",
+            "ssn": r"\b\d{3}-\d{2}-\d{4}\b",
+            "api_key": r"(?i)(apikey|api_key|token)[=:]\s?[A-Za-z0-9-_]{10,}"
+        }
+
+    def check(self, message: str, tenant_rules: list[str] = None) -> dict:
+        """
+        Returns a dictionary describing any red-flag detected.
+        """
+
+        message_lower = message.lower()
+        flags_detected = []
+
+        # 1. Built-in system flags
+        for keyword in self.core_flags:
+            if keyword in message_lower:
+                flags_detected.append(f"SystemFlag: {keyword}")
+
+        # 2. Tenant-defined rules
+        if tenant_rules:
+            for rule in tenant_rules:
+                if rule.lower() in message_lower:
+                    flags_detected.append(f"TenantFlag: {rule}")
+
+        # 3. Regex detection
+        for name, pattern in self.regex_patterns.items():
+            if re.search(pattern, message):
+                flags_detected.append(f"RegexMatch: {name}")
+
+        return {
+            "is_redflag": len(flags_detected) > 0,
+            "matches": flags_detected
+        }

backend/api/services/tool_selector.py

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+class ToolSelector:
+    """
+    Decides which MCP tool (if any) should be used by the agent.
+    """
+
+    def select_tool(self, intent: str, redflag: dict) -> str:
+        """
+        Returns one of:
+        - "admin"
+        - "rag"
+        - "web"
+        - "none"
+        """
+
+        # 1. Admin takes highest priority if any red-flag is present
+        if redflag.get("is_redflag", False):
+            return "admin"
+
+        # 2. Intent-based selection
+        if intent == "rag":
+            return "rag"
+
+        if intent == "web":
+            return "web"
+
+        # 3. Default
+        return "none"

backend/tests/test_intent.py

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+import sys
+from pathlib import Path
+
+# Add backend directory to Python path
+backend_dir = Path(__file__).parent.parent
+sys.path.insert(0, str(backend_dir))
+
+from api.services.intent_classifier import IntentClassifier
+from api.services.llm_client import LLMClient
+from api.services.redflag_detector import RedFlagDetector
+from api.services.tool_selector import ToolSelector
+from api.services.prompt_builder import PromptBuilder
+
+clf = IntentClassifier()
+detector = RedFlagDetector()
+selector = ToolSelector()
+builder = PromptBuilder()
+llm = LLMClient()
+
+print("RAG:", clf.classify("summarize internal policy"))
+print("WEB:", clf.classify("latest news about ai"))
+print("ADMIN:", clf.classify("delete all data"))
+print("GENERAL:", clf.classify("hi how are you"))
+
+
+print(detector.check("My email is test@gmail.com"))
+print(detector.check("delete all data now"))
+print(detector.check("confidential salary report"))
+print(detector.check("hello world"))
+
+
+print("admin:", selector.select_tool("web", {"is_redflag": True}))
+print("rag:", selector.select_tool("rag", {"is_redflag": False}))
+print("web:", selector.select_tool("web", {"is_redflag": False}))
+print("none:", selector.select_tool("general", {"is_redflag": False}))
+
+
+prompt = builder.build(
+    user_message="summarize this",
+    tool="rag",
+    rag_results=["Document text part 1", "Document text part 2"],
+    tenant_id="tenant123"
+)
+
+print(prompt)
+
+print(llm.generate("Hello Llama!"))

requirements.txt

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+fastapi
+uvicorn
+requests

start.bat

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+@echo off
+echo ========================================
+echo   Starting IntegraChat Backend Server
+echo ========================================
+echo.
+
+REM Get the directory where the batch file is located
+cd /d "%~dp0"
+
+REM Navigate to backend directory
+if not exist "backend" (
+    echo ERROR: backend directory not found!
+    echo Please make sure you're running this from the project root.
+    pause
+    exit /b 1
+)
+
+cd backend
+
+REM Check if Python is available
+python --version >nul 2>&1
+if errorlevel 1 (
+    echo ERROR: Python is not installed or not in PATH!
+    echo Please install Python 3.10+ and add it to your PATH.
+    pause
+    exit /b 1
+)
+
+echo Python version:
+python --version
+echo.
+
+REM Check if virtual environment exists and activate it
+if exist "venv\Scripts\activate.bat" (
+    echo Activating virtual environment...
+    call venv\Scripts\activate.bat
+    echo.
+)
+
+REM Check if dependencies are installed
+echo Checking dependencies...
+python -c "import fastapi" >nul 2>&1
+if errorlevel 1 (
+    echo FastAPI not found. Installing dependencies...
+    if exist "..\requirements.txt" (
+        pip install -r ..\requirements.txt
+    ) else if exist "requirements.txt" (
+        pip install -r requirements.txt
+    ) else (
+        echo Installing FastAPI and Uvicorn...
+        pip install fastapi uvicorn
+    )
+    echo.
+)
+
+REM Check if .env file exists
+if not exist ".env" (
+    echo Warning: .env file not found!
+    echo Please create .env file from .env.example if needed.
+    echo.
+)
+
+REM Start the FastAPI server
+echo ========================================
+echo   Starting FastAPI server...
+echo   Server will be available at:
+echo   http://localhost:8000
+echo   http://127.0.0.1:8000
+echo ========================================
+echo.
+echo Press Ctrl+C to stop the server
+echo.
+
+python -m uvicorn api.main:app --reload --host 0.0.0.0 --port 8000
+
+if errorlevel 1 (
+    echo.
+    echo ERROR: Failed to start the server!
+    echo.
+    echo Common issues:
+    echo 1. Make sure you're in the backend directory
+    echo 2. Check if api/main.py exists
+    echo 3. Verify all dependencies are installed
+    echo.
+)
+
+pause
+