Port the DeepSeek, Perplexity, and xAI families

app/MindWork AI Studio/Models/XAI/GrokFamily.cs

@@ -0,0 +1,58 @@
+using static AIStudio.Provider.Capability;
+
+namespace AIStudio.Models.XAI;
+
+/// <summary>
+/// Grok, from the old vision models to the 5 line.
+/// </summary>
+/// <remarks>
+/// The family's own fallback calls functions, and that is deliberate: without it an unknown Grok
+/// version would reach whatever answers for everything and lose tool calling, which every Grok
+/// since the 3 line has. Grok 3 itself needs no rule for the same reason -- the fallback already
+/// says exactly what it is.
+///
+/// Video is not among their modalities. xAI serves audio, image, and video through models and APIs
+/// of their own, and the model pages of the 4.x line say "text, image" and nothing else.
+/// </remarks>
+public sealed class GrokFamily : ModelFamily
+{
+    /// <inheritdoc />
+    public override ModelVendor Vendor => ModelVendor.XAI;
+
+    /// <inheritdoc />
+    public override ModelSource Source => new("https://docs.x.ai/docs/models", new DateOnly(2026, 9, 11), "Ported unchanged from the Grok block of ProviderExtensions.OpenSource.cs.");
+
+    /// <inheritdoc />
+    protected override void Declare(ModelFamilyBuilder builder)
+    {
+        builder.Rule("grok").AsSegment()
+            .Capabilities(TEXT_INPUT | TEXT_OUTPUT | FUNCTION_CALLING)
+            .Apis(CHAT_COMPLETION_API);
+
+        // The old vision models look at pictures and call nothing:
+        builder.Rule("grok").AsSegment().AlsoContains("vision")
+            .Capabilities(TEXT_INPUT | MULTIPLE_IMAGE_INPUT | TEXT_OUTPUT)
+            .Apis(CHAT_COMPLETION_API);
+
+        builder.Rule("grok-3-mini").AsPrefix()
+            .Capabilities(TEXT_INPUT | TEXT_OUTPUT | FUNCTION_CALLING)
+            .Apis(CHAT_COMPLETION_API)
+            .Reasoning(ReasoningSupport.ALWAYS);
+
+        //
+        // The 4 line reads images and always thinks; only the effort can be set. The 4.20 models
+        // need a line of their own because a dot separates versions rather than name parts, so
+        // "grok-4" does not answer for "grok-4.20".
+        //
+        builder.Rule("grok-4").AsPrefix()
+            .Capabilities(TEXT_INPUT | MULTIPLE_IMAGE_INPUT | TEXT_OUTPUT | FUNCTION_CALLING)
+            .Apis(CHAT_COMPLETION_API)
+            .Reasoning(ReasoningSupport.ALWAYS);
+
+        builder.Rule("grok-4.20").AsPrefix().InheritsFrom("grok-4");
+
+        // One member of the 4.20 line answers without thinking, and it says so in its name:
+        builder.Rule("grok-4.20").AsPrefix().AlsoContains("non-reasoning").Inherits()
+            .Reasoning(ReasoningSupport.NONE);
+    }
+}