Use replay to explain or compare recorded work after the live connection ends. Replay does not replace the original terminal result or silently rerun a provider.
Durable records
Kestrel retains session, thread, run, turn, request and correlation identities; profile/provider revisions; budgets; approvals and external-effect results; recovery decisions; evaluation evidence; ordered events; terminal outcomes; memory provenance; Mission Control links; artifacts; and workspace checkpoints.
Replay bundle
A bundle contains the canonical inputs and persisted outputs needed by the selected replay contract, plus release/build identity. It excludes provider credentials, active leases, encrypted continuation state, private reasoning, and unrelated tenant data.
Replay
Deterministic runtime reducers, parsers, state transitions, and recorded tool results can be replayed exactly from canonical evidence. A fresh provider request is provider-dependent and must be labeled as a new execution, not proof that the original run behaved the same way.
Compare live and replayed outcomes
Compare input fingerprint, event order, terminal taxonomy, assistant text, structured output, policy decisions, evidence, and artifact identity. Explain every disagreement by its first owning boundary.
Security and retention
Authorize bundle creation and inspection by tenant, Project, actor, and resource. Apply normal deletion/retention policy and record who exported or inspected the evidence.
Verify replay evidence
Replay a known bundle twice and confirm deterministic records agree. Then remove or alter a required record and confirm validation fails rather than filling the gap heuristically.
Continue with Reliability, Observability, and Evaluations.