AI Agent for Facebook Messenger

The Problem

Customers message a Facebook Page at all hours and expect fast answers. Small teams can't staff Messenger around the clock.

How It Works

1. 01Message received
2. 02Filter
3. 03Load business info
4. 04AI agent replies
5. 05Send via Messenger

What I Built

• Webhook handles both Meta's GET verification handshake and incoming POST messages
• Filter drops events that aren't real customer messages
• Pulls business info from a Google Doc so answers stay on-brand and factual
• AI Agent on Gemini 3.5 Flash with Simple Memory to keep the conversation context
• HTTP Request sends the reply back through the Messenger API

Tools Used

What Was Tricky

Meta verifies a webhook with a GET request before it will send any messages. I split the webhook into a GET branch that echoes the verification challenge and a POST branch for real messages, so the same URL handles both.

Where This Fits