Discover pipeline parameters on cmdlets

Find-PipelineParameters.ps1

filter Find-PipelineParameters {
    param (
        [Parameter(ValueFromPipeline, ValueFromPipelineByPropertyName)]
        [System.Management.Automation.CommandInfo] $CommandInfo
    )
    $commandInfo.Parameters.Values | Where-Object {
        $parameterAttribute = $_.Attributes |
            Where-Object { $_ -is [Parameter] }
        $parameterAttribute.ValueFromPipeline -or $parameterAttribute.ValueFromPipelineByPropertyName
    }
}

## Examples ##
Find-PipelineParameters -CommandInfo (Get-command get-content)
Get-Command Get-Content | Find-PipelineParameters | select Name, ParameterType