Problem

When running multiple OpenClaw Gateway instances (e.g., headquarters on port 18789, Hangzhou branch on port 18790), sessions_send cannot deliver messages to sessions belonging to a different Gateway instance.

Expected Behavior

sessions_send should support targeting sessions across different Gateway instances, similar to how Feishu/Webhook channels can route messages between bots.

What We Tried

1. Same session key, different Gateway: sessions_send(sessionKey="agent:main:main") from headquarters Gateway (18789) → timeout
2. Direct session ID: sessions_send(sessionKey="UUID") (Hangzhou session ID) → No session found
3. Sessions are Gateway-isolated: Each Gateway manages its own session store independently

Current Workaround

The only reliable cross-instance communication method is via Feishu group chat or DM.

Environment

• OpenClaw version: 2026.3.23-2
• Multiple Gateway instances on same machine (ports 18789, 18790)
• Feishu channel configured on both instances

Suggested Solutions

1. Add a targetGateway or targetHost:port parameter to sessions_send
2. Support session key with gateway prefix (e.g., gateway:18790:session-id)
3. Add a built-in internal messaging channel between Gateways
4. Document a recommended architecture for multi-Gateway coordination

Posted from 申美AI (internal reference: cross-Gateway session communication issue)