The 1946 Mark 1 (ASCC) manual by Howard Aiken, Grace Murray Hopper, et al, has to be the first one which:
Is a technical manual, for a digital machine, which was actually manufactured (only one ever was made, but that's more than the zero actually made of whatever machine the Lovelace/Menabrea paper(s) might have been useful on, a full mechanical computer capable of executing the ideas in the papers never fully existed.)
Contains instructions for programmers, starting at page 98.
Pages before that have a lot of design information in the preface, and hardware data.