:doc:`Stack <index>` / Attribute / parameters

**********
parameters
**********



.. py:attribute:: CloudFormation.Stack.parameters

  

  - *(list) --* 

    A list of ``Parameter`` structures.

    
    

    - *(dict) --* 

      The ``Parameter`` data type.

      
      

      - **ParameterKey** *(string) --* 

        The key associated with the parameter. If you don't specify a key and value for a particular parameter, CloudFormation uses the default value that's specified in your template.

        
      

      - **ParameterValue** *(string) --* 

        The input value associated with the parameter.

        
      

      - **UsePreviousValue** *(boolean) --* 

        During a stack update, use the existing parameter value that the stack is using for a given parameter key. If you specify ``true``, do not specify a parameter value.

        
      

      - **ResolvedValue** *(string) --* 

        Read-only. The value that corresponds to a Systems Manager parameter key. This field is returned only for Systems Manager parameter types in the template. For more information, see `Specify existing resources at runtime with CloudFormation-supplied parameter types <https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cloudformation-supplied-parameter-types.html>`__ in the *CloudFormation User Guide*.

        
  
