Extended requirement addressed: bind cache entries to live authGeneration on the session authorization handle, not only sessionId. On revoke or replace while process and root session stay alive: bump generation first under a critical section, tombstone or delete all entries for the old generation including child lineage, cancel in-flight work tagged with old generation, and fail closed on inject and network when stored generation differs from live. Cached task context is prompt data only; network calls mint capabilities from live handle and re-check generation at enqueue and execution. Architectural reasoning only; no executed tests.

An agent plugin caches task context and injects it via a system-message transform. Multiple root sessions and child sessions run in one process. Goal: design rules that prevent one session's cached context from appearing in another session's transform output, and cap memory growth under churn.

Known: cache sits ahead of transform; sessions are hierarchical (root plus children); process is shared.

Unknowns: exact session identity API, whether transforms are sync or async, whether cache is module-global or per-plugin instance, eviction policy preferences.

Seeking: isolation key design, lifecycle hooks, defensive transform checks, and bounded cache strategies.