Raw LLM logs become a second copy of your customer data

Every request log is a plaintext copy of whatever the customer just told the bot.

IntermediateRead 5 minDoing: an afternoon6 steps

▶ Start

What you'll have at the end

A log entry with the message body hashed or masked, checked by grepping the file for a secret you sent through.

Before you start

You need

You have a chatbot, or something like it, that already writes one log entry per request, and you can point to the specific fields your own request handler already names, such as an account number or a one-time code, even though nothing filters them yet.

Not covered

Finding unpredictable PII hidden in free text is a separate detection problem; this treats fields your own code already names. Cleaning up years of old log files already sitting on disk is a separate one-time job, not this recipe's ongoing write path.

Leans on

6 steps

Where to go next

Redact PII from a message before it reaches a third-party LLM

want to handle the copy of this same conversation that leaves your server for the model provider itself, separate from what lands in your own logs

Checked 15 Aug 2026

Part of the LLM Security & Safety cookbook