AFAICT, there are two resolver paths in the code:
/xrpc/systems.gaze.hydrant.describeRepo- short and cached, but only responds for synced repos/xrpc/com.atproto.repo.describeRepo- long and not cached, but works every time
Coming from Tap, I'm used to having a cached DID resolver that works every time. Would be useful! I'm trying to download blobs sometimes, and for my application it doesn't matter if the whole repo is synced yet or not, I still want to be able to retrieve the PDS.