social.grain.unspecced.listPoolGalleries
query not from the namespace authority

Every gallery in a group's pool, newest first. Assembled at request time from the repos of the members who wrote them — a pool space never reaches a firehose, so none of it is in the index — and readable only by a member the group's host issues a credential to.
social.grain.unspecced.listPoolFeed
query not from the namespace authority

Every gallery in every pool the viewer is a member of, newest first. Assembled per viewer at request time: which groups they belong to is a public fact in the index, but what is in each pool is a permissioned space, read with a credential that group's host issues. Nothing here is shared between viewers or cached.
social.grain.unspecced.getPrivateGallery
query not from the namespace authority

Assemble a gallery that lives in a permissioned space. Read from the repos that hold it at request time — space records never reach a firehose, so none of this is in the index.
social.grain.unspecced.listPrivateGalleries
query not from the namespace authority

The viewer's own private galleries, read from the spaces their PDS holds. Authors only: a space tells its members nothing about itself, so an account added to someone else's gallery cannot enumerate it and needs the link.
social.grain.unspecced.getGroup
query not from the namespace authority

A group: a group DID that has declared itself and shows up in Grain as an author whose pool is other people's galleries.