{
  "overall_correctness": "correct",
  "explanation": "No blocking findings: crates/spt-store/src/serving.rs:149-163 uses an fs2-supported write-only handle and a stable appended .lock sentinel; crates/spt-daemon/src/servehost.rs:147-267 and livehost.rs:1282-1336 acquire before loading, fail closed, retain guards through snapshot side effects/publication, and preserve explicit-save/no-op behavior, with no remaining concurrent production-writer gaps found. Source coverage includes the fail-closed unit at servehost.rs:635-651, all three process regressions at crates/spt-store/tests/serving_registry_two_process_int.rs:193-212, and guarded live-daemon fixtures at crates/spt/tests/webserve_attachment_e2e.rs:666-731 and webserve_cross_node_e2e.rs:661-775; the independent contention witness in tests/fixtures/serving_registry_worker.rs:31-58 deterministically rejects a holder with only its OS-lock acquisition disabled, while the documented storage-API-versus-production-schedule limitation remains accurate. traceable-reqs.toml:7749-7752 is active without the obsolete PREP-ONLY comment, documentation correctly requires both broker and brain upgrades, and this was exclusively a text-source review: no files changed and no builds, tests, linters, analyzers, or validation commands run.",
  "confidence": 0.95,
  "findings": []
}