The rules for touch-only effects such as the Psi slight Psychic Stab imply that the attacker must initiate the touch. Is it possible to instead initiate the touch-based attack when receiving a melee hit from an opponent. For example, morph with Psi level 2 holds their action and is hit with a melee weapon by an opponent and then releases their Psychic Stab without having to make their own attack roll? (Can envision something similar if defending using shock gloves or something, though I suppose in that case there'd be a chance of the attacker hitting something other than the gloves.
Exactly what constitutes a "touch"? Must you contact skin? Some part of the opponent's clothing? Anything the opponent is wielding?