Guardrails And Safety medium
Your team logs full prompts and responses for debugging and plans a nightly batch job that redacts emails, phone numbers, and card numbers from the log store. Compliance rejects the plan. What should you do instead?
- A Redact at ingestion before anything is written; by the nightly run, raw PII already sits in log storage, replicas, and sinks.
- B Keep nightly redaction but encrypt logs at rest with managed keys, which satisfies the requirement since only staff can read them.
- C Instruct the model in its system prompt never to repeat PII in responses, so the logged outputs contain nothing to redact.
- D Keep raw logs but cut retention to 24 hours, which bounds the exposure window and makes the nightly redaction job unnecessary.
Answer: A. Redact at ingestion before anything is written; by the nightly run, raw PII already sits in log storage, replicas, and sinks.
**Redaction after logging is too late**: before the batch runs, the data has already been copied to replicas, backups, and log shippers. Redacting in the write path adds per-request latency and can strip context engineers want for debugging. Encryption at rest (B) is tempting, but it controls who reads the data, not whether the data was collected, and every operator with access still sees raw PII. Delayed redaction is acceptable only when logs stay inside a controlled, PII-approved enclave.
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