Umbraco "magic" macro parameters

// In your template:
<umbraco:macro filelocation="~/macroScripts/Default/MetaTags.cshtml" fixedtitle="Site Name" runat="server" />

// Usage of the "fixedtitle" parameter in Razor:
<title>@(!string.IsNullOrWhiteSpace(Model.MetaTitle) ? Model.MetaTitle : Model.Name) | @Parameter.fixedtitle</title>

<meta name="description" content="@Model.MetaDescription" />
<meta name="keywords" content="@Model.MetaKeywords" />