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Interview question · Agent, Tool & MCP Security

An agent proposes a high-value purchase for a user to approve. How do you make sure the approval covers exactly what gets executed?

Freeze the resolved purchase, authenticate the approver and verify the same action at execution. Then handle mutable addresses, simultaneous workers and a supplier timeout without treating a hash as a complete transaction protocol.

hardNewUpdated Nov 2026

Freeze the resolved purchase, authenticate the approver and verify the same action at execution. Then handle mutable addresses, simultaneous workers and a supplier timeout without treating a hash as a complete transaction protocol.

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  1. 01 State the assumptions your answer depends on.
  2. 02 Explain the mechanism and choose a control.
  3. 03 Name a condition that would change your decision.

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What if · the follow-ups in this answer

The answer works through 4 follow-ups like an interviewer would

Alder’s procurement assistant has an approved purchase record. A queue worker will submit it to a supplier, but directory updates and retries can occur before the result is recorded.

  1. What if the supplier account changes under the same directory ID?
  2. What if two workers both read approved and unused?
  3. What if the supplier times out after possibly accepting the order?
  4. Which tests would you require before trusting the binding?

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