Define Semantic Search as a tool that offers itself

app/Tests/Tools/ToolCalling/SemanticSearchToolDefinitionTests.cs

@@ -0,0 +1,48 @@
+using AIStudio.Chat;
+using AIStudio.Provider;
+using AIStudio.Tools.ToolCallingSystem;
+using AIStudio.Tools.ToolCallingSystem.ToolCallingImplementations.SemanticSearch;
+
+namespace AIStudio.Tests.Tools.ToolCalling;
+
+/// <summary>
+/// Checks that the registry takes the definition of Semantic Search the way it is meant.
+/// </summary>
+/// <remarks>
+/// The registry drops a definition it cannot accept with no more than a warning in the log. For
+/// Semantic Search, that would quietly bring back the classic RAG process in every chat. The tool
+/// is offered without anybody selecting it, and only where there are data sources to search: in a
+/// chat, never in an assistant.
+/// </remarks>
+[TestFixture]
+[NonParallelizable]
+public sealed class SemanticSearchToolDefinitionTests : ToolRegistryTestBase
+{
+    [Test]
+    public async Task AChatIsOfferedTheToolWithoutSelectingIt()
+    {
+        var registry = this.CreateRegistry(new TestTool(new SemanticSearchTool().GetDefinition()));
+
+        var runnableTools = await registry.GetRunnableToolsAsync(this.ContextFor(ToolCapableProvider()), [], mayRunTools: true);
+
+        Assert.That(runnableTools.Select(tool => tool.Definition.Id), Is.EqualTo(new[] { ToolSelectionRules.SEMANTIC_SEARCH_TOOL_ID }));
+    }
+
+    [Test]
+    public async Task AnAssistantIsNeverOfferedTheTool()
+    {
+        var registry = this.CreateRegistry(new TestTool(new SemanticSearchTool().GetDefinition()));
+        var provider = ToolCapableProvider();
+        var context = new ToolResolutionContext
+        {
+            Provider = provider,
+            Component = AIStudio.Tools.Components.REWRITE_ASSISTANT,
+            ProviderConfidence = provider.UsedLLMProvider.GetConfidence(this.SettingsManager).Level,
+            ChatThread = new ChatThread(),
+        };
+
+        var runnableTools = await registry.GetRunnableToolsAsync(context, [ToolSelectionRules.SEMANTIC_SEARCH_TOOL_ID], mayRunTools: true);
+
+        Assert.That(runnableTools, Is.Empty, "An assistant has no data sources to search, even when something names the tool.");
+    }
+}