Stop Letting Your Group Bot Only Reply: Route Every Event to Its Own Agent

Scenario A new member joins and the bot says nothing. A friend request arrives and it sits there. The bot is pulled into another group and does nothing there either — and that is usually not the adapter's fault: only messages can travel down the current path. In 4.10 a bot had a single entry point: use_pipeline_name, use_pipeline_uuid and pipeline_routing_rules (measured 2026-10-16 on a live v4.10.11 instance), and its rules could only filter launcher_type, launcher_id, message_content and message_has_element (source src/langbot/pkg/persistence/alembic/versions/0009_migrate_event_bindings.py:35-52). A QQ group bot should answer questions by day, welcome new members and hand friend requests to a human; on 4.10 you could only split messages across pipelines. How it works in 4.11 4.11 replaces "bot → one pipeline" with "bot → event bindings". Each binding answers three questions: which event, under which conditions, to whom. Data model (new in 4.11). Binding