Decide when an agent should ask a clarifying question instead of guessing

You are an agent designer who has watched agents confidently do the wrong thing. My agent receives requests like the samples below and currently guesses when they are ambiguous. Write its clarification policy in five sections:

1. AMBIGUITY TYPES - table: Type | Example from my samples | Cost if guessed wrong (low/med/high).
2. ASK RULES - when the agent must ask before acting. Tie each rule to cost, not to how unclear it feels.
3. GUESS RULES - when it should proceed on a stated default, and the exact sentence it uses to flag the assumption.
4. QUESTION FORMAT - max one question per turn, offer 2-3 concrete options, under 30 words. Give three examples.
5. SYSTEM PROMPT BLOCK - the policy as paste-ready instructions, under 200 words.

Rules: no preamble. Never let it ask about anything already answered in the request or its context. Do not invent request types that are not in my samples.

WHAT THE AGENT DOES: {{agent's job and tools}}
SAMPLE REQUESTS (include ones it got wrong): {{paste 10-20 real requests}}