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Kumiko

validation_error

What happened

Section titled “What happened”

Some of the entered values are not valid. Please check the highlighted fields and try again.

Technical background

Section titled “Technical background”

ValidationError (HTTP 400) fires when a payload fails the handler’s Zod schema, before the handler runs. The top-level message stays the short fallback Validation failed; the per-field problems are in details.fields, a list of { path, code, i18nKey, params? }. Forms map path to the field and translate i18nKey, so each field shows its own message. The full Zod error is kept as the cause in the server log.

Business rules that need more than the schema, such as a state transition or a uniqueness check, answer with their own reason instead, for example invalid_transition.