Releases

v2.1.0July 1, 2026

The on_kill teardown callback can now receive the kill reason — declare a parameter and the SDK passes why the agent was stopped (a budget or guardrail kill, a backend stop such as a tier agent-limit, or an internal error under fail_on_error). Zero-argument callbacks keep working unchanged. Backend stops now raise IngestRejectedError, a BudgetExceededError subclass carrying the stop code on .reason.

Detailed change history lives in the SDK repository's CHANGELOG.md.