Pass commands to an MCU to execute, is there a standardized format?

[tggzzz]

Well, this thread is a great example of how people love to over-engineer things! There is no need here for an embedded script language.

Sticking to the KISS principle, you could use something that is already done and tested, like an embedded scripting language.

Many people with an academic computing background long to create their own language and write their own compiler. The electronic engineering equivalent is creating your own microprocessor.

Those are fun activities with some merit, but in almost all cases the productivity (as defined by skinning a cat) is, um, suboptimal.