Type Alias: SenderPolicy

SenderPolicy = "allowlist" | "unrestricted"

How the sender (From) address is restricted.

"allowlist" is the default and the deny-by-default posture: a send is permitted only from an address the configuration names, either through EmailPluginConfig.allowedSenders or, when that is empty, through the configured sender source (EmailPluginConfig.from as an exact address, EmailPluginConfig.domain as a *@domain wildcard).

"unrestricted" is the explicit opt-out: any From a caller supplies is accepted. Only reach for it when an upstream system already vets the sender.