Why are Android SDK tools divided into “platform-tools” and “tools”?

Question

What does the tool decide to go to a specific directory? As an example, adb was in tools /, but switched to platform-tools /. Why can't they live in the same directory?

Answer 1

platform-tools/ mainly stores binaries that will vary from Windows to OS X to Linux. tools/ mainly contains JAR and shell script / batch files for Java tools.

As to why individual catalogs, I think, make it easier for technicians to distribute and package.