trpc-query-writing-data-violates-idempotency-contract

A tRPC query procedure (GET-equivalent) that writes side effects (e.g., creating notification records) violates the query/mutation contract: queries must be idempotent reads. Beyond correctness, the practical failure is that cron-less reminder systems only fire when a user manually triggers the endpoint — silent delivery failure. Reminder delivery requires a scheduled job (cron or queue), not a lazily-invoked query endpoint.

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• trpc-query-writing-side-effects-breaks-idempotency
• trpc-query-used-for-side-effects-reminder-anti-pattern
• trpc-query-writing-data-breaks-cron-and-idempotency
• trpc-query-procedures-must-be-idempotent-reads-only
• trpc-query-procedure-used-as-mutation-violates-contract
• trpc-query-used-as-mutation-breaks-reminder-delivery
• dependabot-first-cycle-floods-repo-with-prs
• trpc-query-that-writes-violates-idempotency-contract