chore: import upstream snapshot with attribution

dotnet/tests/Foundry.Hosting.IntegrationTests/ToolCallingHostedAgentTests.cs

@@ -0,0 +1,79 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Linq;
+using System.Threading.Tasks;
+using Foundry.Hosting.IntegrationTests.Fixtures;
+using Microsoft.Extensions.AI;
+
+namespace Foundry.Hosting.IntegrationTests;
+
+/// <summary>
+/// Tests that exercise server side tool invocation by a hosted agent. The container
+/// declares deterministic AIFunctions (e.g. <c>GetUtcNow</c>, <c>Multiply</c>) and the
+/// model decides whether to call them based on the prompt.
+/// </summary>
+[Trait("Category", "FoundryHostedAgents")]
+public sealed class ToolCallingHostedAgentTests(ToolCallingHostedAgentFixture fixture) : IClassFixture<ToolCallingHostedAgentFixture>
+{
+    private readonly ToolCallingHostedAgentFixture _fixture = fixture;
+
+    [Fact]
+    public async Task ServerSideTool_IsInvokedWhenPromptedAsync()
+    {
+        // Arrange
+        var agent = this._fixture.Agent;
+
+        // Act
+        var response = await agent.RunAsync("What is the current UTC date and time? Use the GetUtcNow tool.");
+
+        // Assert: response references a timestamp (very loose check; deterministic-ish).
+        Assert.False(string.IsNullOrWhiteSpace(response.Text));
+        Assert.True(response.Messages.Any(m => m.Contents.OfType<FunctionCallContent>().Any()),
+            "Expected at least one FunctionCallContent in the response messages.");
+    }
+
+    [Fact]
+    public async Task ServerSideTool_NotInvokedWhenNotNeededAsync()
+    {
+        // Arrange
+        var agent = this._fixture.Agent;
+
+        // Act
+        var response = await agent.RunAsync("Say hello in one word.");
+
+        // Assert: no tool call expected for a simple greeting.
+        Assert.False(string.IsNullOrWhiteSpace(response.Text));
+        var toolCallCount = response.Messages.SelectMany(m => m.Contents.OfType<FunctionCallContent>()).Count();
+        Assert.Equal(0, toolCallCount);
+    }
+
+    [Fact]
+    public async Task ServerSideTool_MultiTurn_RemembersPriorToolResultAsync()
+    {
+        // Arrange
+        var agent = this._fixture.Agent;
+        var session = await agent.CreateSessionAsync();
+
+        // Act
+        var first = await agent.RunAsync("Multiply 6 by 7 using the Multiply tool. Reply with the result.", session);
+        Assert.Contains("42", first.Text);
+
+        var second = await agent.RunAsync("What was the result of the last multiplication?", session);
+
+        // Assert
+        Assert.Contains("42", second.Text);
+    }
+
+    [Fact]
+    public async Task ServerSideTool_WithArguments_ReturnsExpectedResultAsync()
+    {
+        // Arrange
+        var agent = this._fixture.Agent;
+
+        // Act
+        var response = await agent.RunAsync("Use the Multiply tool with a=12 and b=11. Reply with just the numeric result.");
+
+        // Assert
+        Assert.Contains("132", response.Text);
+    }
+}