The provider id the seat runs on, such as 'openrouter'.
The model id sent to that provider.
A declared vendor, and the baseUrl the call goes to.
Optional vendor?: stringOptional baseThe vendor, lower-cased ('anthropic', 'meta'), or undefined.
Who trained the model a seat ran on, or undefined when that cannot be determined.
opts.vendor(declared on the pool entry or the fixed seat) wins; a native provider on its own endpoint gives its maker, and on a custom base URL (opts.baseUrl, or the provider's URL variable when none is given) gives undefined; a host gives the model id's maker prefix. An empty or whitespace-only URL counts as none, as every call reads one (baseUrlIfSet), so the next source decides.