Agent Skills: frontend-query-mutation

Guide for implementing Dify frontend query and mutation patterns with TanStack Query and oRPC. Trigger when creating or updating contracts in web/contract, wiring router composition, consuming consoleQuery or marketplaceQuery in components or services, deciding whether to call queryOptions() directly or extract a helper or use-* hook, handling conditional queries, cache invalidation, mutation error handling, or migrating legacy service calls to contract-first query and mutation helpers.