Router Steps

Parameters

Parameter	Type	Default	Description
selector	Callable[[StepInput], ...] | Callable[[StepInput, list], ...]	None	Function to select steps dynamically. Can optionally accept step_choices as second parameter
choices	WorkflowSteps	Required	Available steps for selection. Supports nested lists (becomes Steps container)
name	Optional[str]	None	Name of the router step
description	Optional[str]	None	Description of the router step
human_review	Optional[HumanReview]	None	All HITL settings in a single config. See HumanReview Config.
requires_confirmation	bool	False	Pause for user confirmation before executing selected route
confirmation_message	Optional[str]	None	Message shown to user when requesting confirmation
requires_user_input	bool	False	Pause for user to select route(s) instead of using selector. See Router HITL.
user_input_message	Optional[str]	None	Message shown to user when requesting route selection
allow_multiple_selections	bool	False	Allow user to select multiple routes
requires_output_review	bool	False	Pause after the selected route completes to review its output. See Output Review.
output_review_message	Optional[str]	None	Message shown to user during output review
hitl_max_retries	int	3	Max re-executions when an output review is rejected with OnReject.retry
hitl_timeout	Optional[int]	None	Seconds before the HITL pause auto-resolves. See Timeout.
on_timeout	Union[OnTimeout, str]	OnTimeout.cancel	Action when the HITL timeout expires: approve, reject, cancel
on_reject	OnReject	OnReject.skip	Action when rejected: skip, cancel, retry

Selector Return Types

The selector function can return any of the following:

Return Type	Description
str	Step name as string - Router resolves it from choices
Step	Step object directly
List[Step]	List of steps for chaining execution

Selector Function Signatures

Basic Signature

def selector(step_input: StepInput) -> Union[str, Step, List[Step]]:
    ...

Extended Signature (with step_choices)

def selector(step_input: StepInput, step_choices: list) -> Union[str, Step, List[Step]]:
    ...

The step_choices parameter provides access to the prepared Step objects from Router.choices, enabling dynamic selection based on available options.

Async Support

Both signatures support async functions:

async def selector(step_input: StepInput, step_choices: list) -> Union[str, Step, List[Step]]:
    ...