Is there a master list of Tensorflow ops that are differentiable (i.e., will auto-differentiate)?
Two other ways to phrase this:
No, there is no list (you can be the first one to create it). Also as far as I am aware, documentation of each function also does not tell it (tf.size is non-differentiable but does not tell about it).
Apart from the way you suggested, you can also extract this data from the source code. For example all the ops that have gradient implemented, have @ops.RegisterGradient in front of the method declaration. For ops which do not have gradient you will have ops.NotDifferentiable(
Not related, but probably helpful.