The way I see it works, and how I DM it IMC is as follows:
1)
Player says: " I'm going to open that door"
And I go: "You feel no impending danger from the door, but there is strong danger behind the door"
(Ie, no traps in door, nothing accidental is going to happen, like getting the door frame on his head, but behind the door is a nasty CR 20 monster.
2)
Player says "I'm gonna cast Disintegrate on that wizard there"
And I go: "You sense danger in doing that"
(Ie, the enemy wizard happens to have Spell Turning on himself that would turn the disintegrate back to the player)
3)
Player says: "I'm going to walk that narrow bridge to the other side of the chasm"
And I go: "You feel danger in crossing the bridge and greater danger by crossing the chasm"
(Ie, the bridge is old and would crumble by the weight of the player. However, there is a nasty CR 20 Tentacle monster in the chasm that will try to eat everyone crossing the chasm.)
4)
Player says: "I'm going to give this information about the murderer to the mayor."
And I go: "You feel impending danger in doing that"
(Ie, the mayor himself has assigned the murder and if he finds out that players know too much, he will try to eliminate the players right away)
5)
Player says: "I'm going to give a finger to that Solar"
And I go: "Well, nothing dangerous will happen"
(Ie, the Solar just won't be bothered about one finger)
6)
Player says: "I'm gonna jump through that black portal"
And I go either: "Well, no danger in sight" or "Great danger awaits", depending where the portal goes (Outlands and Negative energy plane, respectively)
7)
Player says: "I drink that odd looking stuff from the pool"
And I go "No danger" or "Danger" or "Great danger" , depending what might happen. (Heal, alignment change and Implosion, respectively)
Notice that the warnings that the spell gives, are not completely clear. The player just know that there is danger coming out for him soon.
This 'soon' is the difference that I could see some DMs would have. I usually keep it as immediate. Do something and in 1-5 rounds, something will happen. If the mayor would take a day or two to assign the death of the players, Foresight would not warn about it (IMC). The example above happens only, if the mayor calls his guards and puts the players to jail or tries to kill them.
This is how it should work. And I kinda hate it, as it reveals too much to the players. They always know if there is something bad behind a door, or if ANY action they make will be dangerous to them.
Of course, they sometimes need to brave the dangers to go forward, but at least they know when to prepare and when there is no need.
When this is combined with Find the Path, the 'adventure' becomes a 'tunnel run'

. If they just know the place where they want to go, they will know the shortest way there, know all the mazes and puzzles, if there are any, will know every time when something dangerous if going to happen and have time to prepare.