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Hey
I am having a problem, when I pass a parameter to a flow that does not fit the pydantic model, the on_failure function does not trigger. Anyone faced such thing?

hi <@U06KA65L5EZ> - if your flow never starts, it makes sense to me that your `on_failure` hook would not trigger.

we validate parameters before we create the flow run in the API, so orchestration logic like state hooks never runs

There is any way to run a callback to a validation error like that?

depending on what you need a callback for, you may want to put a `field_validator` / `model_validator` on your model