The export reads ChatGPT's and Claude's undocumented internal web APIs,
which can change shape without notice; the worst failure for a backup tool
is a silent one (skipped/mis-parsed content with no error). Add a `canary`
command + BaseProvider.check_drift() (overridden by ChatGPT/Claude) that
fetches one listing page + one conversation per provider and asserts only
the normalizer's load-bearing fields — not the full response shape, which
churns harmlessly. The top silent risk it guards is a renamed retrieval-tool
author bypassing the hidden-content collapse. ERROR findings exit non-zero;
WARN findings are surfaced but non-fatal so a backup run is never blocked.
Also retires the in-app watch mode and headless StartOS direction from the
roadmap (tool stays a local, manually-run CLI) and updates docs.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>