How to choose face similarity threshold in 1:1 face recognition

I am using this library to build a face recognition service, in the 1:1 face comparison, how do I choose the threshold(0~100%) of similarity to determine that two pictures are the same person, and whether there is a recommended value of similarity

The issue names no file, test, or entry point and asks for a recommended threshold rather than a defined code change. Start by locating the 1:1 face-comparison API and its evaluation or documentation context, then define done as project-specific guidance backed by validation data; maintainer confirmation is needed first.

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