What
A new built-in tool that streams events from background scripts as live notifications in the conversation.
Usage
# Inside a Claude Code session, Claude can use the Monitor tool to:
# - Tail logs for errors
# - Watch for file changes
# - Poll GitHub for new PR comments
# - Stream events from WebSocket listenersDetails
- Each stdout line from the script becomes a notification in the conversation
- Events arriving within 200ms are batched into a single notification
- Supports
persistent: truemode for session-length watches (PR monitoring, log tails) - Supports
timeout_msfor time-limited monitoring - Monitors that produce too many events are automatically stopped with guidance to restart using tighter filters
- Use
TaskStopto cancel a running monitor - Distinct from
Bashwithrun_in_background— Monitor is for the streaming case ("tell me every time X happens"), while background Bash is for one-shot "wait until done"
Evidence
MonitorTool definition (search for "stream events from a background script as live notifications")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.