Added tool calling support (#731)

Co-authored-by: krut_ni <nils.kruthoff@dlr.de>
Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

app/MindWork AI Studio/Provider/Anthropic/AnthropicToolCallingAdapter.cs

@@ -0,0 +1,88 @@
+using AIStudio.Tools.ToolCallingSystem;
+using AIStudio.Tools.ToolCallingSystem.Harness;
+
+namespace AIStudio.Provider.Anthropic;
+
+/// <summary>
+/// Speaks the Anthropic messages wire format for the tool calling loop.
+/// </summary>
+/// <remarks>
+/// Anthropic works in content blocks rather than in separate message kinds: the model's turn is
+/// one assistant message whose blocks may mix text, thinking, and tool uses, and the results go
+/// back as tool result blocks inside a single user message. That difference is what made this
+/// provider hard to support before the loop and the wire format were separated — it is now the
+/// only thing this class is about.
+/// </remarks>
+public sealed class AnthropicToolCallingAdapter(Model chatModel, IList<IMessageBase> baseMessages, string systemPrompt, int maxTokens,
+    IDictionary<string, object> apiParameters, IReadOnlyList<(ToolDefinition Definition, IToolImplementation Implementation)> runnableTools,
+    Func<ChatRequest, CancellationToken, Task<AnthropicResponse?>> executeRequestAsync) : IToolCallingProviderAdapter
+{
+    private readonly List<IMessageBase> internalMessages = [];
+    private readonly List<AnthropicToolResultContent> pendingToolResults = [];
+    private readonly List<AnthropicTool> tools = runnableTools.Select(x => ProviderToolAdapters.ToAnthropicTool(x.Definition)).ToList();
+    private AnthropicResponse? lastResponse;
+
+    /// <inheritdoc />
+    public async Task<ToolCallingRound?> ExecuteRoundAsync(string? finalResponseInstruction, bool includeTools, CancellationToken token = default)
+    {
+        //
+        // The results of the previous round are flushed here rather than when they were recorded:
+        // they all belong in one user message, and only now is it certain that no more are coming.
+        //
+        if (this.pendingToolResults.Count > 0)
+        {
+            this.internalMessages.Add(new AnthropicToolResultMessage([..this.pendingToolResults]));
+            this.pendingToolResults.Clear();
+        }
+
+        var response = await executeRequestAsync(new ChatRequest
+        {
+            Model = chatModel.Id,
+            Messages = [..baseMessages, ..this.internalMessages],
+            System = finalResponseInstruction is null
+                ? systemPrompt
+                : $"{systemPrompt}{Environment.NewLine}{Environment.NewLine}{finalResponseInstruction}",
+
+            MaxTokens = maxTokens,
+            Stream = false,
+            Tools = includeTools && this.tools.Count > 0 ? this.tools : null,
+            AdditionalApiParameters = apiParameters,
+        }, token);
+
+        if (response is null)
+            return null;
+
+        this.lastResponse = response;
+        return new ToolCallingRound(
+            response.GetTextOutput(),
+            response.GetToolUses()
+                .Select(toolUse => new ToolCallingRequestedCall(
+                    toolUse.Id,
+                    toolUse.Name,
+                    toolUse.Arguments,
+                    ToolExecutor.IsValidArgumentsJson(toolUse.Arguments)))
+                .ToList(),
+            []);
+    }
+
+    /// <inheritdoc />
+    public void RecordAssistantTurn()
+    {
+        if (this.lastResponse is null)
+            return;
+
+        //
+        // The blocks go back exactly as they arrived. Thinking blocks in particular have to be
+        // returned unchanged for the model to continue from them.
+        //
+        this.internalMessages.Add(new AnthropicMessage([..this.lastResponse.Content]));
+    }
+
+    /// <inheritdoc />
+    public void RecordToolResult(string callId, string content, bool isError = false) => this.pendingToolResults.Add(new AnthropicToolResultContent
+    {
+        ToolUseId = callId,
+        Content = content,
+        IsError = isError,
+    });
+}