URL: http://github.com/dotnet/extensions/issues/7290
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Most providers now have an API for counting tokens, i.e. submit the full request as you otherwise would, but get back a token count rather than an actual response. We should consider adding an interface for this purpose, e.g.
Task<int> CountTokensAsync(IEnumerable<ChatMessage>, ChatOptions, CancellationToken);It could be implemented by IChatClients that support it and served up from their GetService implementations.