tl;dr: Inference APIs are increasingly returning provider-sealed state—encrypted reasoning tokens, opaque compaction blobs, hidden search results, and encrypted subagent messages—that turns local transcripts into partial views of sessions whose real state lives on provider servers. This breaks session portability, auditability, and user control, locking users into ecosystems even when they nominally "own" their data. The author argues providers should make storage optional, ensure every opaque artifact has a readable handoff representation, and stop treating outside distillation as illegitimate while practicing it internally.