Auto vault of manual vault in first person game?

I'm making a fast paced FP game with emphasis on movement and reflexes (close to Mirror's Edge and Ghostrunner)

I'm currently implementing vault mechanic (climbing on edges) and I can't decide whether I should make it manual (character climbs only if the player presses jump button) or automatic (if there's an edge in front of the character and he's falling, he'll automatically climb on it)

On one hand auto vault seems very convenient and is widely used in other games. But on the other hand it somewhat restricts movement while falling and people start mashing space when near an edge anyway

 

I played through Mirror's Edge 3 times if I remember correctly. I expect such games to only climb/vault while I hold a button (space is perfect for keyboard and mouse setups). Games with too much "auto" movement are super annoying because you end up triggering things unintentionally all the time. It was a constant annoyance to me in Splinter Cell Blacklist.

 

Manual but have plenty of space so it doesnt require precision. Being able to hold or just press once and both working is nice.

I kind of like idea that if you don't press it and just run into wall, you crash. Would be funny but also make timing an actual part of the game that seems designed.

 

A risk with an auto system is that people are doing other things near edges and their character climbs up them when not desired. So my personal preference would be to make it both button press required and that you need to be looking or moving in the right direction, as long as the detection on this is fairly generous and 100% reliable.

Thinking through some use cases...
1 - If I'm standing on a platform next to a ledge I definitely don't want the game to auto-climb the ledge as I'm just moving around. So that's a "no" to making it fully automated.
2 - Lots of players also jump just as a part of being harder targets to hit, so if I'm looking away from the ledge and jumping I also don't want that to climb.
3 - But if I'm looking into the ledge and press the jump button I might want it to climb, but I might also just be trying to get a better look. Undecided here.
4 - If I want to climb it then, personally, I'm going to be looking at it, moving towards it, and press the jump button. So as long as that case can be detected 100% of the time then as a player I'd be happy.

Given 4, my personal gut feel for 3 is to make it not climb without movement input. But that will depend really heavily on the rest of your game, and on your target audience.

 

You maybe could make it so that you either climb with pressing and holding jump + forward movement, or pressing jump and pressing jump again at the ledge without forward movement (assuming the game has no double jump), since both would be a good indication the player wants to do more than just jump up.