A filter path segment ending in [] resolves to the list of every element's
value, so a task can run only when, say, an issue carries a given label:
{path: 'body.issue.labels[].name', op: 'equals', value: 'needs more info'}.
equals, in and startsWith match when any element does, notEquals only when
none equals the value, exists when the list is not empty. Placeholders
accept the same syntax and render the list.

Before this, filters could only compare scalars and arrays satisfied
exists alone, so a GitHub issue_comment hook had to wake the bound thread
on every comment in the repository and let the agent discard the rest.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>