There's a full section of the government website dedicated to this subject, and also a recent act of parliament which in part prepared legislation for it, the Data Use and Access Act 2025 [1]. See my other answer in this thread for the links.

The Digital ID scheme isn't new. The only change is from it being optional to mandatory.

[1] https://www.legislation.gov.uk/ukpga/2025/18/enacted

Thanks for the link - I was aware the government was preparing voluntary ID. I meant the zero proof element specifically as this is the first time I have heard mention of it.

These are referenced in the framework guidance (which is iterative) intended for DVSs. Here for instance:

https://www.gov.uk/government/publications/uk-digital-identi...

If you want a technical explanation of how they work, you will need to loose elsewhere.