Guides & engineering notes

WhatsApp for AI agents and phone systems

Step-by-step guides to connect WhatsApp to Claude, ChatGPT, Cursor, Grok and your PBX, plus the engineering behind it: SIP bridging, the MLow voice codec, webhooks and per-number egress.

The MLow codec in pure Go — a clean-room encoder and decoder for Meta's low-bitrate voice codec. WhatsMCP Engineering.
Audio Codecs Sep 11, 2026 · 13 min read

Rebuilding MLow: WhatsApp's Voice Codec in Pure Go

How we built a clean-room, pure-Go encoder and decoder for MLow — Meta's low-bitrate codec behind billions of WhatsApp, Messenger and Instagram calls: the hybrid SILK/CELT structure, reverse-engineering it against the live library, and frame-exact validation.

By WhatsMCP Engineering Read post