import com.atlassian.servicedesk.api.field.FieldInputValue
import com.onresolve.scriptrunner.runner.customisers.WithPlugin

@WithPlugin("com.atlassian.servicedesk")

def val = FieldInputValue.withValue(10)
log.debug "Value : ${val.value()}"

import com.onresolve.scriptrunner.runner.rest.common.CustomEndpointDelegate
import groovy.json.JsonBuilder
import groovy.transform.BaseScript
import javax.ws.rs.core.MultivaluedMap
import javax.ws.rs.core.Response
import com.atlassian.servicedesk.api.field.FieldInputValue
import com.onresolve.scriptrunner.runner.customisers.WithPlugin

@WithPlugin("com.atlassian.servicedesk")
@BaseScript CustomEndpointDelegate delegate 

doSomething(httpMethod: "GET", groups: ["jira-administrators"]) { MultivaluedMap queryParams, String body ->
    def val = FieldInputValue.withValue(10)
    return Response.ok(new JsonBuilder([abc: val.value()]).toString()).build();
}