needsConfirmation: true with a single-use confirm_token, valid five minutes and bound to a hash of the arguments. A token issued for two recipients cannot be replayed for two hundred.
Response when confirmation is required
confirm_token added within five minutes.
Tiers
The threshold is set per action, not per tool —manage_leads alone spans “add a note” and “delete a lead”, three orders of magnitude apart in consequence. Confirming everything trains people to click through; confirming nothing eventually loses data.