Use NIP-26 to delegate authentication with NIP-42 to have zappers authenticate to payed relays on behalf of the user zapping.

The client would create a NIP-26 time limited delegation for kind 22242 and add it to the NIP-57 zap request. The zapper can then use this delegation to authenticate against payed relays and deliver the kind 9735 note. Relays would need to add a check of the delegation to their auth workflow.

This adds a little more load as as a relay needs to look for a delegation tag before dropping incoming notes. However there is no need to validate the delegation if the pubkey does not belong to a whitelisted user.

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Good idea or bs?