Guardrails And Safety medium
You are building an email agent that can read the user's inbox and send email. A security review worries that an incoming email could contain injected instructions telling the agent to forward the whole inbox to an outside address. Which design best bounds the blast radius?
- A Fine-tune the model on adversarial emails so it learns to refuse forwarding instructions that appear inside message bodies.
- B Scan inbound emails with an injection classifier and drop flagged messages before the agent ever reads them.
- C Log every send action and run a nightly audit job that alerts on messages sent to recipients outside the user's contacts.
- D Gate the send tool outside the model: require user confirmation of recipient and body, and default to known contacts only.
Answer: D. Gate the send tool outside the model: require user confirmation of recipient and body, and default to known contacts only.
The model cannot be the only line of defense, so the **high-impact capability must be gated outside it**. Then a compromised turn cannot cause an unbounded action. The cost is friction on every send, which is acceptable here because sending email is irreversible. Fine-tuning (A) and classifiers (B) lower the attack success rate but never reach zero, and a nightly audit (C) finds the leak only after the data is gone. Audit-only would be reasonable for low-impact, reversible actions.
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- An email assistant has tools to read the inbox, send email, and edit the calendar. To resist injection, the team adopts a dual-LLM design. A privileged planner model issues tool calls but never sees raw email text. A quarantined model with no tool access processes the emails and returns its results as opaque variables, which the planner can only pass along. What is the primary tradeoff the team accepts?
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