Error monitoringSentry, with personal data stripped first
When something breaks we report the error to Sentry so we can fix it. Every report passes through a scrubber on the way out: request cookies and authorization headers are deleted; your email address, username, and IP address are removed; and anything in the attached diagnostics whose name looks sensitive — site or field names, measurements and readings, coordinates, addresses, tokens, passwords — is replaced with [redacted]. Within that attached diagnostic data, any value that looks like an email address is redacted too.
An internal user id stays on the error so we can tell one person's crash from another's. It is not a name or an email, and it is not sent to Google or Vercel.
If the scrubber itself fails, the report is cut down to a bare shell — the exception and nothing else — rather than sent unscrubbed.