Jenkinsfile with depenedent stage on choosed agent from parameter

Jenkinsfile

def AGENT_LABEL = null

node('master'){
    stage('pre'){
        AGENT_LABEL = env.SLOT
    }
}

pipeline {
    agent none
    parameters {
        choice choices: ['Agent1', 'Agent2'], description: 'Some description ', name: 'SLOT'
    }
    stages {
        stage('Stage on selected agent) {
            agent {
                label "${AGENT_LABEL}"
            }
        }
    }
}