The metadata for langchain4j is called

langchain4j-mongodb

For Hibernate Mongo it's mongo-hibernate

The proposal should be

1. keep the name as small as possible to save the payload size (for example remove mongo prefix or suffix and just framework name e.g hibernate or langchain4j)
2. consistent between other drivers
3. handle the case when framework is owned by mongodb or not (for example hibernate is maintained by mongo while langchain4j mongodb is maintained by langchain4j team)