It uses the official Claude CLI:
claude --dangerously-skip-permissions -p --output-format stream-json --verbose --include-partial-messages --system-prompt <scrubbed prompt> --model <model> --resume <session-id> "<user message>"
It uses the custom system prompt and scrubs any mention of openclaw from it (https://news.ycombinator.com/item?id=47656695). Note that --bare mode requires you to use API tokens, so this doesn't use that.
It adds a new provider called glueclaw with three models: glueclaw/glueclaw-opus, glueclaw/glueclaw-sonnet, and glueclaw/glueclaw-haiku.