Apologies for the simple question, just starting out... I'm having trouble understanding how I can update something in the graph.cool data - I have

type Item { id ID! @isUnique connected: Boolean }

and I'd like to toggle

connected

- What would the query be to do so?

To change data on the server, you use GraphQL mutations. In this case, you will want to use the updateItem mutation

I think the part that is confusing me is the

updateItem

bit -- does graph.cool (or graphql) automatically 'add' add<name> update<name> delete<name> or is that something I'm supposed to be setting up somewhere?

Yes, Graph.cool generates a whole load of mutations for your API. For every type X you will have createX, updateX and deleteX