## Base StructureDefinition for ParameterDefinition
Type: The parameters to the module. This collection specifies both the input and output parameters. Input parameters are provided by the caller as part of the $evaluate operation. Output parameters are included in the [GuidanceResponse](/content/docs/api/fhir/resources/guidanceresponse/index.html).

### Elements
| Name       | Required | Type             | Description |
|------------|----------|------------------|-------------|
| id         |          | string           | Unique id for inter-element referencing<br>Details<br>Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. |
| extension  |          | [Extension](/content/docs/api/fhir/datatypes/extension/index.html)[] | Additional content defined by implementations<br>Details<br>May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.<br>There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
| name       |          | code             | Name used to access the parameter value<br>Details<br>The name of the parameter used to allow access to the value of the parameter in evaluation contexts. |
| use        | ✓        | code             | in | out<br>Details<br>Whether the parameter is input or output for the module. |
| min        |          | integer          | Minimum cardinality<br>Details<br>The minimum number of times this parameter SHALL appear in the request or response. |
| max        |          | string           | Maximum cardinality (a number of *)<br>Details<br>The maximum number of times this element is permitted to appear in the request or response. |
| documentation |       | string           | A brief description of the parameter<br>Details<br>A brief discussion of what the parameter is for and how it is used by the module. |
| type       | ✓        | code             | What type of value<br>Details<br>The type of the parameter. |
| profile    |          | canonical        | What profile the value is expected to be<br>Details<br>If specified, this indicates a profile that the input data must conform to, or that the output data will conform to. |

- [Elements](/content/docs/api/fhir/datatypes/parameterdefinition#elements/index.html)