Port the DeepSeek, Perplexity, and xAI families

app/MindWork AI Studio/Models/DeepSeek/DeepSeekFamily.cs

@@ -0,0 +1,77 @@
+using static AIStudio.Provider.Capability;
+
+namespace AIStudio.Models.DeepSeek;
+
+/// <summary>
+/// DeepSeek, from V3 to V4, including R1 and the checkpoints distilled from it.
+/// </summary>
+/// <remarks>
+/// One family for all of it, and bound to no provider: DeepSeek publishes its models as open
+/// weights and offers them on its own platform under the very same names, so a rule written once
+/// answers wherever the model turns up. The old code arrived at that by having its DeepSeek
+/// function call the open weights function, which is one of the loops this rebuild is undoing.
+///
+/// The distills are the case the whole priority question came from. They are Llama and Qwen
+/// checkpoints fine-tuned on R1 answers, so they carry "r1" in their name and would be read as R1
+/// itself -- which would promise the tool calling they lost together with R1's chat template. Here
+/// the rule for them is the R1 rule with one condition more, and that alone decides it.
+///
+/// Point releases behind a dot need a line of their own, as everywhere: "deepseek-v4" does not
+/// answer for "deepseek-v4.1", because a dot separates versions rather than name parts.
+/// </remarks>
+public sealed class DeepSeekFamily : ModelFamily
+{
+    /// <inheritdoc />
+    public override ModelVendor Vendor => ModelVendor.DEEP_SEEK;
+
+    /// <inheritdoc />
+    public override ModelSource Source => new("https://api-docs.deepseek.com/", new DateOnly(2026, 9, 11), "Ported unchanged from the rules in ProviderExtensions.DeepSeek.cs and the DeepSeek block of ProviderExtensions.OpenSource.cs.");
+
+    /// <inheritdoc />
+    protected override void Declare(ModelFamilyBuilder builder)
+    {
+        builder.Rule("deepseek").AsSegment()
+            .Capabilities(TEXT_INPUT | TEXT_OUTPUT)
+            .Apis(CHAT_COMPLETION_API);
+
+        // The V3 line answers directly and calls functions:
+        builder.Rule("deepseek-v3").AsPrefix().Inherits()
+            .Capabilities(FUNCTION_CALLING);
+
+        //
+        // From V3.1 on there is a thinking mode which the request turns on, and V3.2 added tool
+        // calling inside it. The gateways write these either as "deepseek-v3.1" or as
+        // "deepseek-chat-v3.1", so the version alone is what is looked for.
+        //
+        builder.Rule("deepseek").AsSegment().AlsoContains("v3.1").InheritsFrom("deepseek-v3")
+            .Reasoning(ReasoningSupport.OPTIONAL);
+
+        builder.Rule("deepseek").AsSegment().AlsoContains("v3.2").InheritsFrom("deepseek-v3")
+            .Reasoning(ReasoningSupport.OPTIONAL);
+
+        builder.Rule("deepseek-r1").AsPrefix().InheritsFrom("deepseek-v3")
+            .Reasoning(ReasoningSupport.ALWAYS);
+
+        // The distills kept the chat template of the model they were built from, so none of the
+        // tool calling R1 itself was trained for survived:
+        builder.Rule("deepseek-r1").AsPrefix().AlsoContains("distill").Inherits()
+            .Removes(FUNCTION_CALLING);
+
+        builder.Rule("deepseek-v4").AsPrefix().InheritsFrom("deepseek-v3")
+            .Reasoning(ReasoningSupport.ON_BY_DEFAULT);
+
+        builder.Rule("deepseek-v4").AsPrefix().AlsoContains("vision").Inherits()
+            .Capabilities(MULTIPLE_IMAGE_INPUT);
+
+        //
+        // The two aliases of DeepSeek's own platform. They name a mode rather than a model: both
+        // point at the current flash model, one with thinking and one without. Exactly these
+        // names and no others -- "deepseek-chat-v3.1" is a gateway's name for a version, not this
+        // alias.
+        //
+        builder.Rule("deepseek-chat").AsExact().InheritsFrom("deepseek-v3");
+
+        builder.Rule("deepseek-reasoner").AsExact().InheritsFrom("deepseek-v3")
+            .Reasoning(ReasoningSupport.ALWAYS);
+    }
+}