From their README

Install the 1Password CLI and turn on the integration in 1Password Preferences → Developer → Connect with 1Password CLI.

1Password preferences


Interact with your 1Password items via the Search Keyword (default: 1p). Set the actions for each modifier in the Workflow’s Configuration.

Alfred search for 1p

Uncommon but useful actions, such as toggling vaults, can be accessed via :1pextras.

Alfred search for :1pextras

Results for managing vaults

A Fallback Search is included.

To report a problem, run !1pdiagnostic.