Checkpoint & Migration

Checkpoint MUST:

• Bind to session_id + fencing token

• Include step_index

• Include last tool result hash

• Preserve deterministic continuation

Resume MUST:

• Acquire valid lease

• Respect idempotency semantics

• Continue only after validating prior receipts

Migration MAY:

• Move session between executors

• Preserve fencing semantics

• Emit migration audit events