I am sure this question is no longer relevant, but in case anyone is interested is still here:
the "script" field in json should be the actual script not the name of the script. in your case script_id will be correct, you should also add the language name if the default value has not been changed.
curl -XPOST 'http://localhost:9200/customer92/listbuilder/a10/_update' -d ' { "script_id":"summarization", "lang": "groovy" }'
See: Indexed Scripts and API Update for more details.
source share