Progress and Cancellation

Long-running tools need ordered progress that can survive UI reconnects and runtime replay.

A progress record SHOULD include sequence, status, message, percent, current step, total steps, elapsed time, byte or line counters, partial result refs, artifact refs, and timestamp.

Progress classes

Initial status values:

• queued
• started
• running
• waiting_for_permission
• waiting_for_input
• backgrounded
• partial_result
• completed
• failed
• canceled

Cancellation facts

Cancellation has separate facts:

1. cancel_requested - a caller asked to cancel.
2. cancel_acknowledged - the executor acknowledged the request.
3. abort_reason - user interruption, sibling error, timeout, fallback, or runtime shutdown.
4. canceled or cancel_failed - the execution reached a terminal outcome.

Do not imply cancellation support from a button in UI. The execution profile must declare it.