A replacement of the signature help functionality from atom-ide-ui. When you're calling a function, it can help you understand the parameters or information about the function you’re calling.
Signature help is activated when:
Once signature help has been triggered, the provider will be queried immediately with the current cursor position, and then repeatedly upon cursor movements until a null/empty signature is returned.
Returned signatures will be displayed in a small datatip at the current cursor. The highest-priority provider with a non-null result will be used.
A set of characters that will trigger signature help when typed. If a null/empty set is provided, only manual activation of the command works.