Diagnostic cogitate runs now persist to an ephemeral non-journal directory that is cleaned up, instead of writing journal/.cache/cogitate-history — the bounded health probe writes nothing under the journal. The internal `diagnostic` access tier stays available at runtime but is rejected for talent-authored configs, so a talent can no longer land in a no-tools/normal-preamble inconsistent state. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>