Custom Person action which can send and receive data

[Bilal_K]

I am new to marketo and i am looking to modify/customise/add an action in the Database -> All People section. 

I want my custom option to work in a way when user select record(s) and click my option, it sends the selected data to my API and the response received will update fields in the Person(s) records. 

Does marketo allows us to create custom actions? Is there any developer guide to do the above process? (probably any alternate way to achieve this?) 

Many thanks !

[SanfordWhiteman]

This is the Webhook feature. See the docs and many, many Nation posts on this.