n8n ManyChat WhatsApp Webhook: OpenAI Reply, Brevo CRM, Slack Alerts

ManyChat WhatsApp replies powered by OpenAI—then synced to Brevo and escalated to Slack for HOT leads

This n8n workflow connects ManyChat WhatsApp Webhooks to an automated AI reply, upserts lead details into Brevo CRM, and can notify your Slack SDR team when a lead is scored as HOT—while immediately returning 200 OK to avoid ManyChat’s 10-second timeout.

What this workflow does

• Receives a ManyChat POST webhook and instantly responds with a JSON handshake (HTTP 200) using respond to webhook.
• Extracts subscriber + message context from the ManyChat payload.
• Calculates a lead score and tier based on the payload details (as implemented in the workflow logic).
• Generates a WhatsApp-ready reply with OpenAI using Chat Completions and gpt-4o-mini.
• Upserts the contact into Brevo CRM with lead attributes such as WHATSAPP_ID, LEAD_SCORE, LEAD_TIER, INTEREST, and BUDGET.
• Sends the reply back to the user via ManyChat’s sendContent API for a WhatsApp callback message.
• Optionally escalates HOT leads to Slack using an incoming webhook, including a direct wa.me chat link.

Use cases

• Automate instant WhatsApp responses for ManyChat subscribers using OpenAI, without risking webhook timeouts.
• Keep your sales pipeline accurate by syncing WhatsApp leads to Brevo CRM with scoring and tier fields.
• Trigger immediate SDR follow-up for high-intent users by sending Slack alerts when leads are marked HOT.

Technical details

• n8n nodes: webhook, if, code, http request, respond to webhook (plus sticky note).
• Required environment variables: MANYCHAT_API_KEY, OPENAI_API_KEY, BREVO_API_KEY, SLACK_WEBHOOK_URL.
• OpenAI: Chat Completions with gpt-4o-mini.
• ManyChat: Uses webhook handshake + sendContent to send WhatsApp callback messages.

Ideal for n8n automation engineers and SaaS operators building WhatsApp lead handling with AI, CRM sync, and Slack-based hot lead escalation.