Clear definition of requirements missing

engineers shall be enabled to fully understand, build and modify the design only by the given documentation

This is very broad and could depends very much on knowledge and experience. some questions that came to me:

• Should the project include assembly instructions?
• If it doesn't, how much time should it take to collect the information from the 3D-Model?
• If it does, should it always be 100% synchronized with the 3D-Model?
• What should be explained in the BOM? Should I be able to find a suitable part with those information only or do is it fine to have e.g. the suitable versions of an arduino board in the code section rather than the BOM?