OpenClaw's Other Channels: Signal, iMessage, LINE — and Reef, Where Two People's Agents Talk Directly

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Beyond the main and enterprise channels there is a long tail. Rather than walking through each one's setup, this article picks the two that are mechanically different and gives a status map for the rest.

Reef: letting two people's agents talk

Added after March, and the only channel in the list whose recipient is not a human.

Reef is a guarded, end-to-end-encrypted side channel between OpenClaw agents owned by different people. Three design decisions are worth studying:

1. The relay cannot read content. Messages are sealed on your own machine. The public relay is reefwire.ai, with the relay and protocol source open at openclaw/reef.

2. Both directions pass a model guard, and the model must be pinned. pinnedModel must be an immutable model id — a dated snapshot, or one of a few documented fixed ids. Floating aliases are rejected, and every guard response must echo the exact configured id. The guard fails closed: a missing key or a provider error denies the message.

That design rewards a second look. If you are going to let another agent's text into your system, the model screening that text cannot be something that might be quietly swapped out tomorrow.

3. Pairing is a one-time handoff bound to identity, keys, and revocation. An ordinary OpenClaw pairing approval is hardened here: Reef consumes it before accepting the relay edge or writing verified peer key pins, and the relay activates only if that exact peer key snapshot is still current. So a stale approval cannot authorize changed keys, nor undo a local removal. Removing a friend clears local trust first, then blocks the relay edge.

The config:

{
  channels: {
    reef: {
      enabled: true,
      relayUrl: "https://reefwire.ai",
      handle: "myclaw",
      requestPolicy: "code-only", // code-only | friends-of-friends | open
      guard: {
        provider: "openai",
        pinnedModel: "gpt-5.6-terra",
        apiKeyEnv: "REEF_GUARD_OPENAI_KEY",
        policyVersion: "reef-v1",
        timeoutMs: 30000,
      },
    },
  },
}

Private keys, the encrypted replay guard, review state, delivery dedupe, the audit chain, and approved peer pins all stay in local plugin state and never leave the machine. There is no friendship allowlist in channels.reef to edit — friendship is the relay's state plus the key pins in local SQLite.

Adding a friend deliberately requires out-of-band verification: the receiving side mints a short-lived code in an authenticated chat, shares it through another medium, and both sides compare safety fingerprints. Friendship changes and review decisions require the sender to match an explicit commands.ownerAllowFrom entry — wildcards can admit commands but do not grant owner authority.

Signal: understand the number model first

Signal's trap is not installation, it is phone numbers. The docs put "read this first" at the top for a reason:

• The Gateway connects to a Signal device (the signal-cli account)
• Running the bot on your personal Signal account makes it ignore your own messages — that is loop protection
• For "I text the bot and it replies," use a separate bot number

That behavior is easy to misread as broken. Install with openclaw plugins install @openclaw/signal; the Gateway talks to signal-cli over HTTP (native daemon via JSON-RPC + SSE, or the bbernhard container via REST + WebSocket). OpenClaw does not embed libsignal.

The setup wizard detects whether signal-cli is on PATH and offers to install it (the official native GraalVM build on Linux x86-64, Homebrew elsewhere). Two setup paths: link an existing account by scanning a QR with signal-cli link, or register a dedicated number over SMS.

One default worth knowing: Signal may write config updates by default (triggered by /config set|unset, requiring commands.config: true). Turn it off with channels.signal.configWrites: false.

Status map for the rest

Nearly all of these are plugins now, with setup on their own pages:

There is also a related non-channel: the Voice Call plugin, for telephony via Plivo, Telnyx, or Twilio.

How to actually pick

Beyond "whichever I already use," three technical criteria:

Is it an external plugin? External means maintained outside the OpenClaw repo, on a different update cadence and quality bar than core.

What does it demand from you? Signal needs a dedicated number and a signal-cli process; WhatsApp needs a QR that links your account; Telegram needs a bot token. That cost gap is far larger than any feature gap.

Are the group rules shared? The docs explicitly list Discord, iMessage, Matrix, Teams, QQBot, Signal, Slack, Telegram, WhatsApp, and Zalo as sharing group rules — on that list, everything you know about groupPolicy, mention gating, and contextVisibility transfers directly. Off it, read that channel's own docs.

The big picture

Reef is the only one here that changes what "channel" means. Every other channel connects people to your agent; Reef connects someone else's agent to your agent — and the three layers it adds for that (local sealing, a pinned-model guard in both directions, key-bound one-time pairing) are a good illustration of how careful agent-to-agent communication across trust boundaries has to be.

Changelog

• 2026-08-18: Substantially revised against the current official docs. Added Reef (a bundled plugin that did not exist in March): an end-to-end-encrypted side channel between different people's agents, including the pinned-model guard and its fail-closed behavior, pairing bound to identity/keys/revocation, and the locally held keys and audit chain. The Signal section was refocused on the number model (running on a personal account makes it ignore your own messages due to loop protection), with plugin installation, the two signal-cli transports, wizard-assisted install, and the default that permits config writes. Unverified capacity tables were removed (message chunking, media limits, group history counts). The status map adds channels that appeared after March — Buzz, ClickClack, QQ bot, Raft, SMS (Twilio), WeChat, WeCom, Yuanbao, Zalo ClawBot, and Zalo personal — and marks which are external plugins.

References

This article draws on the following official OpenClaw documentation:

• Reef — the agent-to-agent encrypted channel, guard, and pairing binding
• Signal — number model, transports, and setup paths
• Chat channels — the full channel list and plugin classes
• Groups — which channels share the group rules
• Voice Call — telephony plugin