Bridge Protocol (Legacy)

The Bridge protocol is a **legacy** node transport (TCP JSONL). New node clients should use the unified Gateway WebSocket protocol.

If you're an operator or building a node client, use the Gateway protocol.

See [Gateway protocol](/gateway/protocol).

Note: Current OpenClaw does not provide a TCP bridge listener. This page remains for historical reference.

Legacy bridge.* config keys are no longer part of the config schema.

• Security boundary: the bridge exposes a small allowlist instead of the full gateway API surface.
• Pairing + node identity: node admission is owned by the gateway and tied to a per-node token.
• Discovery UX: nodes can discover gateways via Bonjour on LAN, or connect directly over a tailnet.
• Loopback WS: the full WS control plane stays local unless tunneled via SSH.

• TCP, one JSON object per line (JSONL).
• Optional TLS (when bridge.tls.enabled is true).
• Legacy default listener port was 18790 (current builds do not start a TCP bridge).

When TLS is enabled, discovery TXT records include bridgeTls=1 plus bridgeTlsSha256 so nodes can pin the certificate.

1. Client sends hello with node metadata + token (if already paired).
2. If not paired, gateway replies error (NOT_PAIRED/UNAUTHORIZED).
3. Client sends pair-request.
4. Gateway waits for approval, then sends pair-ok and hello-ok.

hello-ok returns serverName and may include canvasHostUrl.

Client → Gateway:

• req / res: scoped gateway RPC (chat, sessions, config, health, voicewake, skills.bins)
• event: node signals (voice transcript, agent request, chat subscribe, exec lifecycle)

Gateway → Client:

• invoke / invoke-res: node commands (canvas.*, camera.*, screen.record, location.get, sms.send)
• event: chat updates for subscribed sessions
• ping / pong: keepalive

Legacy allowlist enforcement lived in src/gateway/server-bridge.ts (removed).

Nodes can emit exec.finished or exec.denied events to surface system.run activity. These are mapped to system events in the gateway. (Legacy nodes may still emit exec.started.)

Payload fields (all optional unless noted):

Payload fields (all optional unless noted):

• sessionKey (required): agent session to receive the system event.
• runId: unique exec id for grouping.
• command: raw or formatted command string.
• exitCode, timedOut, success, output: completion details (finished only).
• reason: denial reason (denied only).

• Bind the bridge to a tailnet IP: bridge.bind: "tailnet" in ~/.openclaw/openclaw.json.
• Clients connect via MagicDNS name or tailnet IP.
• Bonjour does **not** cross networks; use manual host/port or wide-area DNS‑SD when needed.

Bridge is currently **implicit v1** (no min/max negotiation). Backward‑compat is expected; add a bridge protocol version field before any breaking changes.