This question was originally part of How does Augury work exactly?, but moved here to clean up.
The Augury spell says:
By casting gem inlaid sticks, rolling dragon bones, laying out ornate cards, or employing some other divining tool, you receive an omen from an otherworldly entity about the results of a specific course of action that you plan to take within the next 30 minutes.
What does the "30 minutes" exactly apply to?
- Initiating the course of action;
- Completing the course of action;
- The result.
Imagine the party are about to sign a contract which gives them an immediate advantage.
NPC: "Yes, of course you can have this artifact! Since the Great Wizard passed away, the Staff of the Magi has just been sitting here. None of us known how to handle it. Better you put it to good use. Just sign here, and it's yours to keep."
The offer sounds too good to be true. What's the catch? To find out if there is any, the Cleric casts Augury with the stated course of action to sign the contract on the spot.
- If they'd sign the contract and immediately get the staff, and there would be no negative effects, then the answer would abviously be "Weal".
- What if the contract needs to be signed in blood by means of some magical ritual that takes longer than 30 minutes? The course of action is started immediately but not completed in time. Would the answer be "Weal" or "Nothing"?
- Assuming the contract is signed immediately - what if the staff is locked up in a safe place, and it will take until the next morning before it can be delivered? The good result will not be there until after the 30 minute limit. Would the answer be "Weal" or "Nothing"?
- Let's say there is some fine print in the contract, stating the signatories sell their soul into slavery of Asmodeus after death. Assuming the staff is given within 30 minutes, the good stuff happens within the time limit, the bad stuff does not. Would the answer be "Weal" or "Weal and woe"?
In our group, we've ruled that the 30 minutes only applies to initiating the course of action, no matter when the results come. I would give "Weal and woe" in that last case, the Augury would provide protection against the fine print.
In answers I am looking for your experience how to best handle this spell in practice.