> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pysquirrels.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Parameter

> Base type for parameter widgets returned from APIs

Abstract base class for all parameter widget classes. In user code, `Parameter` is typically seen as the common return type for parameter widgets you access in `context.py` and other helpers.

Concrete parameter widgets are created by Squirrels based on your parameter configuration and returned from Squirrels APIs; you should not instantiate `Parameter` directly. Use one of the concrete implementations:

* [SingleSelectParameter](/references/python/parameters/singleselectparameter)
* [MultiSelectParameter](/references/python/parameters/multiselectparameter)
* [DateParameter](/references/python/parameters/dateparameter)
* [DateRangeParameter](/references/python/parameters/daterangeparameter)
* [NumberParameter](/references/python/parameters/numberparameter)
* [NumberRangeParameter](/references/python/parameters/numberrangeparameter)
* [TextParameter](/references/python/parameters/textparameter)

When defining parameters or working with them at runtime, use the concrete classes from the `parameters` module rather than `Parameter` itself.

If `Parameter` is needed for type annotation, it can be imported from the `squirrels.types` or `squirrels` module.