Summary:
On Ubuntu host tc1-kenobi, OpenClaw host-side ACP appears correctly installed and active, but ACP spawns from a Telegram-bound assistant session fail immediately with:
ACP runtime backend is not configured. Install and enable the acpx runtime plugin.
Host-side evidence:
• @openclaw/acpx installed from ClawHub
• plugin enabled
• openclaw plugins inspect acpx shows Status: loaded
• openclaw plugins list shows acpx enabled
• /home/cmb/.openclaw/extensions/acpx/node_modules/.bin/acpx --version returns 0.6.1
• ~/.openclaw/openclaw.json contains:
• acp.enabled = true
• acp.backend = "acpx"
• acp.dispatch.enabled = true
• plugins.entries.acpx.enabled = true
• gateway restarts cleanly
• gateway logs show:
• embedded acpx runtime backend registered lazily
Critical mismatch:
When ACP spawn is attempted via sessions_spawn(runtime="acp", ...), it fails immediately with the “not configured” error, and no corresponding ACP request/error appears in the host gateway logs.
Conclusion:
The failure appears to happen upstream of the host gateway/runtime, not on the Ubuntu host itself.
Environment:
• OpenClaw: 2026.5.7
• Host: Ubuntu
• Surface: Telegram direct session