OpenClaw's canonical convention is to emit metadata envelopes (chat_id,
sender, reply target, …) as SEPARATE user-role messages folded into the
openai-completions request right after the real one — `extractLatestUserMessage`
skips those whole.
Fabric.OpenclawPlugin's dispatch does not split: it passes metadata
blocks and the real user content as ONE merged user-message body,
separated by blank lines. With the prior filter that meant the entire
turn was dropped with "no user message found" (HTTP 400) because the
first line matched a sentinel — the actual prompt sitting after the
metadata blocks never reached the bridge.
When the whole-body check fails for a single-message body, walk past
leading sentinel-prefixed blocks (sentinel header + optional ```json
code fence + blank-line separator) and use whatever non-metadata block
follows. Falls back to the previous "skip entirely" semantics when the
body is metadata-only.
End-user symptom that surfaced this: every contractor agent (Claude /
Gemini) subscribed to a Fabric channel silently failed to reply to
sub-discussion messages during recruitment — fabric dispatch said
"completed" in 1.6s but trajectory had `assistantTexts: []`,
`terminalError: non_deliverable_terminal_turn`,
`errorMessage: "400 \"no user message found\""`. Surfaced
recruiting developer1 on prod-t2 2026-05-31.
hzhang
0f49edf59c