The ACP fixture configured read-only as the deployment default for both parent and child. Its delegated write therefore remained denied even with inheritance disabled, so the scenario could not fail on the regression it claimed to protect.
Delete the overlay, scenario registration, sessions, prompt, and 473-line tool-schema sidecar. The Loader-booted headless snapshot remains the real composition guard: only its parent carries read-only while the deployment default is workspace-write, so removing inheritance makes the child write reach disk and fails the test.
Keeping one discriminating snapshot avoids 662 lines of duplicated fixture data and makes the review evidence correspond to the actual security boundary.
The parent implementation introduced sandboxMode and approvalPolicy as generic SessionHeader fields, then propagated those fields through both persistence backends, session-query indexes, collision checks, policy-specific seed-boundary folds, catalogs, and a broad test matrix. That storage plane is unnecessary: Session already accepts a validated constructor seed, and persistence captures that seed when the session is announced before committing its first batch.
Capture each parent override synchronously at delegation, append source-tagged sandbox/mode and approval/policy records after the optional fork prefix, and create the child with that combined seed. Keeping header.seedLength at the original fork-prefix length preserves lineage while ordinary last-event-wins folds make the inherited records outrank stale parent history and remain subordinate to later child switches. Unswitched parents still stamp nothing, so children continue to follow deployment defaults.
Remove the generic header fields and every persistence/query/schema branch built around them. Collapse the inheritance suite from ten leaking scenarios to four owned-context cases covering real filesystem confinement, stale fork precedence, delegation-time capture, and the no-override path. The assembled headless snapshot now asserts the persisted inheritance event directly.
This keeps the security behavior while restoring policy ownership to the existing event log and deleting the speculative durability machinery that the original tests did not exercise.
Retarget the feature branch to the current master tip without rewriting its existing review history. Keeping this as a dedicated merge checkpoint makes the later simplification diff attributable to the stacked child rather than mixing base movement with design changes.
Resolve the identified-message API drift in the feature tests by constructing complete user messages, reading the nested tool-result message shape, and adapting the prompt-submit listener signature. Preserve both sides of the user-approval conflict: master’s createUserMessage wrapper and the feature’s inherited-policy attribution.
Regenerate the Cordis and persistence catalogs, re-record the session README pair, and refresh the affected ACP/headless fixtures so derived artifacts describe the merged source rather than either parent in isolation.
Validated with the focused policy/session/persistence/query suites (430 tests), focused ACP/headless snapshots (3 tests), build, doc-sync (25 gates), lint, hygiene, and git diff checks.
The self-referential inspect tool surfaces Session's public API in its
transcript; the construction-boundary field added in bc8512d17 now
appears there. Keyless refresh; only the affected scenario re-recorded.
The local PTY readiness poll held its inferred_idle fallback for exactly
one pollIntervalMs after a prompt marker, so a bash foreground handoff
that lands on the silence boundary only wins the exact stdin_read
attribution when the kernel publishes it inside that single poll. On a
slow or loaded host it does not, and the attribution flips.
handoffGraceMs replaces the hardcoded one-poll window as a validated,
deployment-owned config field defaulting to 500ms, rejected at load when
it cannot contain one readiness poll. Real-shell tests that interrupt a
send now assert the session is usable again rather than which readiness
tier observed the handoff, because no fixed grace removes the race.
