By activating this simple silver ring, the wearer can benefit from invisibility, as the spell.
Faint illusion; CL 3rd; Forge Ring, invisibility; Price 20,000 gp.
Usually, a ring’s ability is activated by a command word (a standard action that does not provoke attacks of opportunity) or it works continually. Some rings have exceptional activation methods, according to their descriptions.
If no activation method is suggested either in the magic item description or by the nature of the item, assume that a command word is needed to activate it. Command word activation means that a character speaks the word and the item activates. No other special knowledge is needed.
A command word can be a real word, but when this is the case, the holder of the item runs the risk of activating the item accidentally by speaking the word in normal conversation. More often, the command word is some seemingly nonsensical word, or a word or phrase from an ancient language no longer in common use. Activating a command word magic item is a standard action and does not provoke attacks of opportunity.
Ok... so if I get this straight, A ring of invisibility is activated by a command word (a standard action that does not provoke attacks of opportunity) and then it affects the wearer as the spell for 3 minutes (1 min/lvl - CL 3rd). Upon striking an opponent the spell ends and the wearer has to spend another standard action (command word) in order to activate it anew, if he so wishes.
Also, the wearer has the option to speak the command word (standard action) any time during those 3min, so as to "recharge" the duration... as per
Same Effect with Differing Durations: When the same effect is cast more than once on the same target, the durations of the effects don’t stack. Each effect’s duration elapses normally.
Since Invisibility is Dismissible (D) as well as a spell that requires a verbal component, and since:
If the Duration line ends with "(D)," you can dismiss the spell at will. You must be within range of the spell’s effect and must speak words of dismissal, which are usually a modified form of the spell’s verbal component. If the spell has no verbal component, you can dismiss the effect with a gesture. Dismissing a spell is a standard action that does not provoke attacks of opportunity.
...the wearer has the option to dismiss the ring's powers by speaking those "words of dismissal" (another command word) by taking a standard action that does not provoke attacks of opportunity.
Now, I assume that when the user removes the ring from his finger, the effect ends. Another take on this would be that the effect ends once the duration expires, no matter if the user keeps on wearing the ring. RAW does not specify what happens in such a case, even though it seems more logical that the effect ends upon removing the ring from the finger.
The action it takes to wear/remove rings, is not specified either, although it is probably a move action [like drawing/sheathing a weapon - Switch hands with an item (RC, p8)] that does not provoke an AoO (like switch hands with item).
...is this ok or am I missing something?