Build an AI Email Assistant Agent – Next.js + Supabase + OpenAI/Claude

We're looking for an experienced AI/full-stack engineer to help build an AI-powered email assistant using Next.js, Supabase, and modern LLMs such as Claude and OpenAI. The goal is to create an intelligent email agent that connects to a user's Gmail account, understands incoming emails, drafts context-aware replies, and can optionally send emails automatically. Core Features Gmail Integration Secure OAuth authentication with Gmail Read and process incoming emails Monitor new emails in near real time Maintain conversation/thread context AI Reply Generation Generate high-quality email replies using Claude and/or OpenAI Multiple reply tones, for example: Professional Friendly Concise Formal Casual Allow users to provide additional instructions before generating a reply (e.g. "decline politely", "ask for a meeting next week", etc.) Support conversation history for more relevant responses Sending Modes The agent should support two operating modes: 1. Approval Mode AI drafts the reply User reviews and edits if needed User approves before the email is sent 2. Autonomous Mode AI automatically generates and sends replies based on configured rules Users should be able to define when autonomous replies are allowed Calendar Integration Connect to Google Calendar Detect meeting requests, appointments, deadlines, and date/time references from emails Create calendar events automatically when appropriate Avoid duplicate events Request clarification only when the email lacks enough information User Dashboard Connect/disconnect Google account Configure AI preferences Select default reply tone Toggle between Approval and Autonomous modes View email activity and AI-generated replies Manage AI instructions and automation rules Tech Stack Next.js Supabase (Auth, Database, Edge Functions if appropriate) OpenAI API Anthropic Claude API Gmail API Google Calendar API Ideal Experience We're looking for someone with experience in: AI agents LLM integrations Prompt engineering Gmail API Google Calendar API OAuth authentication Next.js Supabase Background jobs and asynchronous processing Building production-ready AI applications Please Include When applying, please share: Similar AI agent projects you've built Experience with Gmail and Google Calendar APIs Experience with OpenAI and/or Claude Your proposed architecture for this system Estimated timeline Fixed-price or hourly rate