You cannot — not with the model alone. It gives you spans + types, not identity.
You need to do that part yourself after the model runs. The filter gives you spans;
for each one, assign a stable ID (PERSON_1, PERSON_2) and keep
{PERSON_1: "Harry", PERSON_2: "Ron"} next to the document. Swap IDs in
before the LLM call, swap originals back in the reply.
Scoping that map to a document/project keeps the same person consistent
across calls, so Harry stays PERSON_1 instead of becoming PERSON_3 the
next time he's mentioned.
(Disclosure: I'm building a Mac privacy tool, RedMatiq, that does exactly this.
The mapping layer turned out substantially harder than detection.)
I'm using GLM 5.1 for the last two weeks as a cheaper alternative to Sonnet, and it's great - probably somewhere between Sonnet and Opus. It's pretty slow though.