I have read all the questions for the same problems and I have tried everything but nothing is working for me when I try to add android platform for cordova.
-Possible solution for those who encounter this error
I had this error and it did relate to the path variables. I thought I had everything set correctly, but I was missing a portion.
First check by typing the command android into command line. If the SDK isn't opened you have not set the variables and/or path correctly.
You should have 3 (or 4 if you have separate android ones) variables.
ANT_HOME, JAVA_HOME and ANDROID_HOME
ANDROID_HOME should point to the sdk. If you (like I did) downloaded the bundle which includes eclipse, you need to have this variable point to the sdk folder inside the android bundle folder, not the android bundle folder itself (eg. C:\Dev\adt-bundle-windows\sdk)
You need to add %ANDROID_HOME%\tools and %ANDROID_HOME%\platform-tools to your path. Along with the link to the ANT bin folder and jdk bin.
I strongly urge you to triple check that all variables are correctly set AND that all four parts are added to the path.