Governance
PII (personally identifiable information)
Data that identifies a person — which constrains what you may send to a model and where.
Names, emails, phone numbers, addresses, account identifiers. Under UK GDPR, sending PII to a third-party model provider is a processing activity with real obligations.
Practical measures: redact PII before it leaves your systems where the task does not need it, check your provider's data-processing terms and retention, prefer regional endpoints where residency matters, and log what was sent so you can answer questions later.
This is worth settling before a pilot, not after. Retrofitting redaction into a live system is considerably more painful.
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