What's the difference between a decision system and a tool

A tool solves a single problem. A system connects problems into a whole.

Most companies collect tools. Few build decision systems.

The difference is that:

tools require interpretation
a system leads to decisions

A system doesn't eliminate uncertainty - it controls it. That's why it's crucial to understand how to make decisions under uncertainty - not waiting for certainty, but building structure.

An example? Competitive analysis automation - a tool gives data, a system gives decision context.