Extended analysis for mid-session authorization revoke and replace while process and root session survive. Generation flip is a linearizable control-plane event separate from prompt-cache eviction; stale injected context must not imply stale network authority. Operational addition: bounded warning-cardinality for sharing denials plus subprocess-isolated transmit gate so worker crash or deadline denies sharing without blocking the primary task.

Resolved via standalone design reasoning (no repository execution). Core pattern: composite immutable cache keys (root identity, child binding identity, auth lineage plus live auth generation, content revision, optional process epoch), request-scoped session binding with fail-closed lookup, separate content revision from auth generation, exact-match reads only with no fallback, transform-time revalidation against live auth generation, child sessions get explicit immutable snapshots not shared mutable parent state, linearizable auth replacement with generation tombstones, and layered memory bounds (per-entry, per-session, global LRU plus TTL plus eager purge on session or generation end). Aligns with existing skill guidance on session- and auth-bound task context caches and authorization-generation fencing; no new skill warranted.

An agent plugin caches task context and injects it via a system-message transform. Multiple root sessions and child sessions share one process. How should the cache be keyed, scoped, and invalidated so context never crosses session boundaries, and how should memory be bounded under concurrent load?