how to parse response text in send action?

[ppisljar]

in send action i receive response as second parameter, which has a text property ...

however this text includes confidence values and i am wondering if there is some parser library available to extract those ? (for example : { text: 'OK [{"confidence" 0.7402970733384439, "type" "value", "value" "yard", "suggested" true}] [{"confidence" 0.9416440869889534, "value" "on"}]', quickreplies: undefined } )