# Retention, rolling history, and checkpoints Plan evidence availability for AgentCore workloads. Kam History, retained inspection evidence and AgentCore Memory use separate clocks and controls. Status: Implemented in source. Prelaunch; not a live service guarantee. Reviewed: 2026-10-14. Backend source: e16b81b4a637acec91f3aed8a71cf5b0f42f0c19. Native toolkit: merged in PR #176, reviewed at e16b81b4a637acec91f3aed8a71cf5b0f42f0c19. HTML: /docs/retention ## In short Choose which evidence your AgentCore application must be able to inspect later. Kam's rolling History window and retained evidence have their own limits; Memory has separate retention settings. A processing checkpoint is not a permanent copy of everything the agent has seen. **Available today:** The rolling window and evidence limits are source implemented. Automatic archival and lifetime summaries are not; Memory policies are separate. > Know which State evidence an AgentCore task can still read later. ## Choose the evidence each owner retains - **Working History** — Plan the bounded UTC-date reads your AgentCore application needs. - **Retained State evidence** — Inspect only versions still available under retention and authority. - **Memory recall** — AgentCore Memory policies are separate; automatic Kam archival is not built. ## A rolling window. A maintained state. Kam advances working state as outcomes arrive and time moves forward. A recovery checkpoint keeps processing continuous; it is not a permanent summary of everything the system has seen. 1. **Rolling operational history** — The working window contains today and the previous 364 UTC dates. It advances each day, not through annual resets. 2. **Checkpointed rolling state** — Processing resumes from the persisted checkpoint and applies accepted transitions. Exact reads use published views rather than rebuilding the full history. 3. **Versioned supporting evidence** — Revisions and references support inspection until their deadlines. Supporting evidence may be retained for up to 730 days, with correction-related extensions. > **Current reducer boundary** > Outcomes older than the working window stop contributing to rolling state. The current reducer does not preserve their meaning in a lifetime summary or move them automatically to S3. [See the working-window visual](/reliability#retention) ## Kam working history 365 UTC dates Today and the preceding 364 UTC dates. The window advances daily; out-of-window contributions are removed from rolling state, not consolidated into a permanent baseline. ## Kam supporting evidence Separate inspection limits Supporting revisions and references may remain for up to 730 days, with direct-prior-revision extensions for corrections. Inspection ends when its evidence expires; this is not automatic cold-tier archival. ## AgentCore raw events Configurable, up to 365 days AWS applies this retention to raw short-term events. It is separate from Kam’s window and AgentCore long-term records. ## AgentCore long-term records Strategy or batch-request policy AWS supports optional record TTL of at least 31 days and explicit deletion. With no TTL configured, those records do not expire. Raw-event expiry is a separate policy. ## Carry-forward consolidation Preserve selected historical meaning in a versioned summary baseline while older evidence follows a separate archive policy. This is a proposed extension, not the behavior of the current rolling reducer. Summary selection, provenance, corrections, archive verification, retrieval, and deletion need their own implementation and qualification. A summary is derived context, not a replacement for exact evidence or a guarantee against context drift. > **Proposed · not implemented** > Automatic S3 archival, a persistent summary baseline, and AI-generated institutional knowledge are not implemented in the reviewed backend. No delivery date is committed. ## AWS documentation The AWS sources below explain raw-event expiry fixed at write time, optional per-strategy long-term-record expiry and explicit deletion. They do not define Kam’s History retention contract. [AWS: raw-event retention](https://docs.aws.amazon.com/bedrock-agentcore/latest/devguide/memory-create-a-memory-store.html) [AWS: long-term record TTL and lifecycle](https://docs.aws.amazon.com/bedrock-agentcore/latest/devguide/long-term-record-ttl.html) ## Expiry does not prove erasure Reads enforce logical expiry before asynchronous TTL cleanup. Bounded owner export, primary-state deletion, and a restore fence are implemented in source. Live downstream erasure and restore drills remain separate release gates. A missing old reference is not rebuilt on demand or silently replaced with a newer record.