An action returns the instance of Writer plugin with Writer methods
The instance object contains all the actions that's specified since before with the intention to get a single access point rather than retrieving multiple actions.
{article:{create:()=>void{/* creates a new article */},open:(uuid)=>void{/* open article with passed uuid */},copy:(uuid)=>void{/* opens a modal to make a copy of chosen article */},preview:(uuid)=>void{/* opens a preview of chosen article */}},config:{get:()=>Promise{/* get current writer configuration */},core:()=>Object{/* get current writer core configuration */},additional:()=>Object{/* get current writer configuration */}},loadableComponents:{config:(name)=>Object{/* get the configuration for that loadable component */},config:()=>Array{/* get all loadable components config */}}}
Preview also has a second optional parameter. This is a function supposed to handle custom images in the case where current configured ICP does not match the one where the images of the preview are supposed to be fetched from.