Auto Registration adding a host to a host group dynamically based on meta data

[Qshar]

I am trying to get a host to be added to the correct hostgroup based on which hostgroupID it provides in the auto registration process. I have several hundred hostgroups (so creating a rule for each does not scale well) and all my servers will belong to only 3 of the groups. Two groups are static for all servers, but the 3rd depends on what hosgroupID it returns in the metadata.
Is there a way to have it dynamically select the host group to add this server to based on the value contained in the host metadata?

[cyber]

Trigger a script from that autoreg action, feed it with needed info ({HOST.HOST}, {HOST.METADATA}) and let it do the group assignment over API.