This page is an attempt at document requirements for official Debian images (CD/DVD, Live CD/DVD, Cloud, etc.). It is work in progress, and not final. But the current listing outlines recommendations for people willing to provide such images with Debian's blessing.
A. the image includes only software available in Debian
B. the image generation process is controlled solely by Debian
C. the image generation tools are maintained inside Debian and/or by a Debian team, using usual Debian recommended practices
D. the images most provide a user experience (in terms of default choice of packages, or of default configuration) identical to other means of installing Debian. Differences must be documented and justified.
E. all cloud-related images have to be built on Debian infrastructure (for instance Salsa or casulana.d.o/petterson.d.o machines). This is to avoid risks that some cloud providers might inject their code.