An unwritable state path raised and took the whole canary down. That is the
worst possible trade for a monitoring tool: it reports nothing at all, and
reports it silently. State is an optimisation for transition detection; the
probing is the point.
Found by fat-fingering an env var, which is exactly how it would happen in
production.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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