Hmm. Problem still unknown. I tried the three steps.
Ricks-MacBook-Pro:HelloWorld rickhedin$ adb kill-server
Ricks-MacBook-Pro:HelloWorld rickhedin$ tns run android
Executing before-prepare hook from /Users/rickhedin/work/170625/HelloWorld/hooks/before-prepare/nativescript-dev-typescript.js
Found peer TypeScript 2.2.2
Project successfully prepared (android)
Searching for devices...
Starting Android emulator with image android2
Waiting for emulator device initialization..............
Cannot run your app in the native emulator. Increase the timeout of the operation with the --timeout option or try to restart your adb server with 'adb kill-server' command. Alternatively, run the Android Virtual Device manager and increase the allocated RAM for the virtual device.
Ricks-MacBook-Pro:HelloWorld rickhedin$ tns doctor
Verifying CocoaPods. This may take more than a minute, please be patient.
. . .
. . .
No issues were detected.
Ricks-MacBook-Pro:HelloWorld rickhedin$ android
The "android" command is deprecated.
For manual SDK, AVD, and project management, please use Android Studio.
For command-line tools, use tools/bin/sdkmanager and tools/bin/avdmanager
Invalid or unsupported command ""
It just seems as though the instructions don't correspond to the current version of software.