structuredOutput issue with Zod primitives

I have noticed an issue: calling an agent.generate in 0.20.X recently I have noticed that giving a

structuredOutput

structuredOutput

schema

schema

option which is a Zod primitive (for example:

schema: z.string()

schema: z.string()

instead of

schema: z.object({ text: z.string() })

schema: z.object({ text: z.string() })

. This breaks every time with a validation error for me.

String is an example, but it also has issues with number(), etc.