Constant MAX_JSON_BODY 

pub const MAX_JSON_BODY: usize = _; // 2_097_152usize

The most of one response body this workspace will hold in memory to read it, when the response comes from a server nothing here operates.

Two mebibytes – the same magnitude didbot-serve’s own MAX_REQUEST_BODY already treats as a safe amount of one JSON payload to hold in memory, on the inbound side of this same server. A DID document or a page of an operator’s own records has no business costing more than one write this server would itself accept costs.