A6 GSM/GPRS module as a GPRS shield

Hello,

Is the class representing Arduino official GSM/GPRS shields documented somewhere?

Background:

I am currently have a working setup of Arduino with AiThinker’s A6 GSM/GPRS module.

I wanted to use the GPRS functionality for sending MQTT messages and I found a few libraries online, but they all depend on specific shields. After digging around a little bit, I realised that most only depend on the software interface provided by those shield like EthernetClient etc.

So, if I can make a library for A6 which provides a similar interface to these MQTT libraries, it could work seemlessly.

But I wasn’t able to find any documentation of the software interface (class definition) of Arduino GSM or GPRS shield. Of course, I did find the library reference (Arduino - GSM), but then didn’t seem readily usable for my purpose.

Is there a minimum specification that I should implement to have the same functionality as an official shield?