If your group has a design document then you are already way ahead of the pack. I’ve written the first design documents that many companies ever had and no they were not all startups.
Not many developers like to write, even fewer can write clearly and thoroughly. It’s a skill worth cultivating.
At my last collaborative gig (I detest the use of “team” in reference to software development, it sounds so sporty) I insisted on doing a design document for each and every nontrivial feature, getting the concurrence of the other participants, if I could get them to read it. One of the others tried to do the same; he pasted a class definition into a document, each line treated like a paragraph, no outline, not Introduction, just a title, and there he was stuck.
I no longer work in onsite jobs, I would not be able to get any work done with the incessant interruptions and the layers of useless process (“scrum” adds nothing), I only work from home as a freelancer and at the moment I am doing technical writing instead of coding.
I would raise one small point contrary to the above. True, don’t expect a major accomplishment right away, however whether acknowledged or not we are all on probation for the first two weeks so I always endeavor to show some kind of result as early as I can, even if it’s outside my nominal area, to establish that I can achieve, to get past the anxiety of probation on both sides of the relationship.