“Not clear enough” is certainly an accusation that can be levelled at the Open-AT documentation! 
For example:
Meaning & use of the A&D Cell ID:
wavecom.com/modules/movie/sc … .php?t=703
Inadequate definition of Call Events & sequences:
wavecom.com/modules/movie/sc … .php?t=709
Open-AT “Under the Hood”
wavecom.com/modules/movie/sc … .php?t=275
The ADL User Guide really doesn’t tell you how to actually use the API; it merely gives a brief description of the available calls.