Nostr Filter Designer

Overview

Construct correct REQ filters for Nostr relay queries. The filter syntax has subtle semantics around AND/OR combination, tag matching, and multi-filter subscriptions that agents consistently get wrong without explicit guidance.

When to use

• The task is to build Nostr REQ filters for querying relay data.
• The user needs exact filter semantics for AND/OR behavior, tag constraints, time windows, or multi-filter subscriptions.
• The problem is retrieving the right events—threads, zaps, feeds, replies, reactions—not publishing them.
• The output should be one or more valid filter objects or REQ messages.

Do NOT use when: