Source note

AgingBench: AI Agents Age Too

AI AgentsAgent ReliabilityMemory SystemsBenchmarkingLongitudinal Evaluation

AgingBench tests whether long-lived AI agents stay reliable as their memory and state change after deployment. A frozen base model can still fail when the agent harness compresses, retrieves, revises, or maintains state over time.

  • Day-one benchmarks evaluate freshly initialized agents and miss failures that appear after many sessions.
  • Persistent agents accumulate summaries, memories, revised facts, and maintenance events, so reliability depends on the full memory pipeline.
  • Operators need to know whether a failure comes from writing, retrieval, or utilization so repair targets the right component.
  • AgingBench defines four aging mechanisms: compression aging, interference aging, revision aging, and maintenance aging.
  • It runs longitudinal agent scenarios across repeated sessions, then checks how reliability changes over time.
  • It uses temporal dependency graphs to track which stored facts and derived states should affect later answers.
  • It uses paired counterfactual probes to diagnose failures at the write, retrieval, and utilization stages of the memory pipeline.
  • It tests runner-controlled and autonomous agents across multiple models and memory policies.
  • The paper reports 7 scenarios, 14 models, multiple memory policies, and over ~400 runs spanning 8 to 200 sessions.
  • The benchmark covers both runner-controlled and autonomous agents.
  • Behavioral tests can stay clean while factual precision decays; the excerpt provides no exact precision scores.
  • Derived-state tracking can collapse sharply within a single model; the excerpt gives no per-model numeric collapse rate.
  • The same wrong answer can require different repairs depending on whether the diagnostic profile points to write, retrieval, or utilization failure.