I respectfully disagree.
I believe you are confusing complex raional thinking with simple planning.
Usage of tools has little to no relevance on the ability to plan.
As with most things there is a gradient of abilities, not a simple "On/Off".
Simians have better planning ability than dogs, cats or hamster, but that does not imply that the dogs, cats, or hamsters have no such ability.
Instinct is a powerful motivator, but I think it is overemphasized in animal behavioral analysis. Studies in recent years have shown animals often act contrary to instinct, and think about things, and yes, even perform simple planning.
Instinct is an ancient "catch-all" for those who thought animals were souless automatons. Animals are really much more amazing than that.
I've seen my dog get angry at us, pause for a moment, then run off to the living room and
deliberately pee on the couch in an effort to get back at us. (Most times he would even wait for us to follow him into the room, so that we could see him do it) That is a form of planning. And when a dog had been house trained for 6 years and does this, it is quite obvious that there is more going on inside that head than instinct.
Edit: fixed spelling (Thanks for pointing that out, I KNEW it looked wrong!)