BizAgent

AI-Powered Receptionist for Service-Based Businesses

Overview

BizAgent is a cross-platform mobile application that gives service-based small businesses — real estate agencies, dental clinics, consultancies, and more — a 24/7 AI-powered receptionist. Users interact with an intelligent chatbot that answers FAQs, qualifies leads, validates appointment availability, prevents double bookings, and writes confirmed appointments directly to a Google Sheet acting as a zero-cost CRM.

Features

Conversational AI Booking — Powered by Google Gemini 2.5 Flash, the chatbot guides users from inquiry to confirmed appointment in a single session
Lead Qualification — Collects name, email, and desired service before booking
Smart Scheduling — Validates against business hours and checks the Google Sheet for conflicts to prevent double bookings
Google Sheets CRM — Every confirmed booking is appended as a new row (Name, Email, Service Type, Date/Time) — zero database cost
Prompt Injection Resistance — System prompt guardrails keep the bot strictly in its receptionist role
Offline Resilience — Failed bookings are cached locally via AsyncStorage and retried on next launch
Network Awareness — Connection banner appears when offline; chat input is disabled until reconnected
Easy Client Onboarding — Swap the business profile JSON and Google Sheet ID to deploy for a new client in minutes
Configurable Rate Limits — Server-side sliding window rate limiting protects Gemini free-tier quotas (RPM / TPM / RPD)
Dark Mode by Default — Slate Professional design with teal accent, crafted for a modern corporate aesthetic

Demo

Showcase: Automatic Google Sheets Integration

Watch how the AI handles the conversation to book an appointment, and how it seamlessly syncs the confirmed booking directly into the business's Google Sheet in real-time.

Google-Sheet-Preview

Landing Screen	Chat Greeting	Chat Conversation

Continue Conversation	Booking Confirmed

Tech Stack

Layer	Technology
Mobile Client	React Native 0.81 · Expo SDK 54 · TypeScript · React 19
UI Framework	React Native Paper (Material Design 3) · react-native-gifted-chat
State Management	React Context + `useReducer`
Backend	Node.js 24 · Express 5 · Vercel Serverless Functions
AI	Google Gemini 2.5 Flash (`@google/genai`)
Database	Google Sheets API (`google-spreadsheet`)
Auth	Google Service Account · API Key (`X-API-Key` header)
Infrastructure	Vercel Hobby (free) · Expo Go / EAS Build

Architecture

┌──────────────────┐         HTTPS          ┌─────────────────────────┐
│                  │ ◄────────────────────►  │   Vercel Serverless     │
│   React Native   │    POST /api/chat       │                         │
│   Expo Client    │    POST /api/book       │  ┌──────────────────┐   │
│                  │    GET  /api/health      │  │  Express Router  │   │
│  ┌────────────┐  │                         │  └────────┬─────────┘   │
│  │ AppContext  │  │                         │           │             │
│  │ useReducer │  │                         │  ┌────────▼─────────┐   │
│  └────────────┘  │                         │  │   Rate Limiter   │   │
│                  │                         │  └────────┬─────────┘   │
│  ┌────────────┐  │                         │           │             │
│  │ AsyncStore │  │                         │  ┌────────▼─────────┐   │
│  │  (retry)   │  │                         │  │   Gemini 2.5     │   │
│  └────────────┘  │                         │  │   Flash API      │   │
└──────────────────┘                         │  └────────┬─────────┘   │
│           │             │
│  ┌────────▼─────────┐   │
│  │  Google Sheets   │   │
│  │  API (CRM)       │   │
│  └──────────────────┘   │
└─────────────────────────┘