Each channel has one gotcha that stops you cold: WhatsApp's login is QR-only and hard to do remotely, Telegram bots ship with Privacy Mode on so they never see group messages (and you must remove and re-add the bot after changing it), and Discord needs Message Content Intent or it receives nothing from servers.
The most interesting entry here is Reef — an end-to-end-encrypted side channel between OpenClaw agents owned by different people. Messages are sealed on your machine, screened in both directions by a pinned-model guard, and the relay operator can never read the content. It ships bundled.
OpenClaw supports 31 chat channels, but only WebChat lives in core — even Slack and WhatsApp are plugins you install. And group safety has two independent axes: allowlists govern who can trigger the agent, not which quotes and history the model sees. That second one is contextVisibility, and it defaults to wide open.
Channels are a special kind of MCP server that push CI failures, monitoring alerts, and Telegram messages directly into a running Claude Code session — and Claude can answer back through the same channel via a reply tool. This post breaks down the channel contract, two-way replies, security gates, and install requirements.