chore: add a test that uses the .NET SDK in the agent code

sampleapps/AnnotationsSample/Agent.cs

@@ -2,14 +2,17 @@
 // SPDX-License-Identifier: Apache-2.0
 
 using System.ComponentModel;
+using System.Reflection;
+using System.Runtime.InteropServices;
+using System.Text.Json;
+using Amazon.S3;
 using AWS.AgentCore;
 using AnnotationsSample.Models;
 using Microsoft.Extensions.AI;
-using Microsoft.Extensions.Logging;
 
 namespace AnnotationsSample;
 
-public class Agent(IChatClient chatClient, ILogger<Agent> logger)
+public class Agent(IChatClient chatClient, IAmazonS3 s3Client, ILogger<Agent> logger)
 {
     [AgentCoreHandler]
     public async Task<string> HandleInvocation(
@@ -20,7 +23,12 @@ public async Task<string> HandleInvocation(
         logger.LogInformation("Invocation — SessionId={SessionId}, RequestId={RequestId}",
             context.SessionId, context.RequestId);
 
-        var agent = chatClient.AsAIAgent(tools: [AIFunctionFactory.Create(GetWeather), AIFunctionFactory.Create(GetAppInfo)]);
+        var agent = chatClient.AsAIAgent(tools:
+        [
+            AIFunctionFactory.Create(GetWeather),
+            AIFunctionFactory.Create(GetAppInfo),
+            AIFunctionFactory.Create(GetS3BucketCount)
+        ]);
         var session = await agent.CreateSessionAsync(cancellationToken: cancellationToken);
         var response = await agent.RunAsync(request.Prompt ?? "Hello!", session, cancellationToken: cancellationToken);
 
@@ -38,13 +46,36 @@ static string GetWeather([Description("The city or location to get weather for."
     static string GetAppInfo()
     {
         var isAot = typeof(object).Assembly.Location == string.Empty;
-        return System.Text.Json.JsonSerializer.Serialize(new
+        return JsonSerializer.Serialize(new
         {
-            appName = System.Reflection.Assembly.GetEntryAssembly()?.GetName().Name ?? "Unknown",
+            appName = Assembly.GetEntryAssembly()?.GetName().Name ?? "Unknown",
             isNativeAot = isAot,
-            framework = System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription,
-            architecture = System.Runtime.InteropServices.RuntimeInformation.OSArchitecture.ToString(),
-            os = System.Runtime.InteropServices.RuntimeInformation.OSDescription
+            framework = RuntimeInformation.FrameworkDescription,
+            architecture = RuntimeInformation.OSArchitecture.ToString(),
+            os = RuntimeInformation.OSDescription
         });
     }
+
+    [Description("Returns the number of S3 buckets in the AWS account. Use this when asked about S3 buckets or AWS resources. This uses the AWS SDK credential chain to authenticate.")]
+    async Task<string> GetS3BucketCount()
+    {
+        try
+        {
+            var response = await s3Client.ListBucketsAsync();
+            return JsonSerializer.Serialize(new
+            {
+                bucketCount = response.Buckets.Count,
+                bucketNames = response.Buckets.Select(b => b.BucketName).ToList()
+            });
+        }
+        catch (Exception ex)
+        {
+            return JsonSerializer.Serialize(new
+            {
+                error = ex.GetType().Name,
+                message = ex.Message,
+                innerError = ex.InnerException?.Message
+            });
+        }
+    }
 }

sampleapps/AnnotationsSample/AnnotationsSample.csproj

@@ -12,6 +12,7 @@
         <ProjectReference Include="..\..\src\AWS.AgentCore.SourceGenerator\AWS.AgentCore.SourceGenerator.csproj"
                           OutputItemType="Analyzer"
                           ReferenceOutputAssembly="false" />
+        <PackageReference Include="AWSSDK.S3" Version="4.0.14" />
     </ItemGroup>
 
 </Project>

sampleapps/AnnotationsSample/Startup.cs

@@ -1,6 +1,7 @@
 // Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 // SPDX-License-Identifier: Apache-2.0
 
+using Amazon.S3;
 using AWS.AgentCore;
 using AWS.AgentCore.Extensions;
 using Microsoft.AspNetCore.Builder;
@@ -16,5 +17,7 @@ public void ConfigureServices(WebApplicationBuilder builder)
         {
             options.ModelId = "global.anthropic.claude-opus-4-7";
         });
+
+        builder.Services.AddAWSService<IAmazonS3>();
     }
 }

test/AWS.AgentCore.IntegrationTests/Infrastructure/DockerHelper.cs

@@ -97,9 +97,23 @@ public static async Task<string> PushToEcrAsync(
         var fullUri = $"{ecrRepositoryUri}:{remoteTag}";
         Console.Error.WriteLine($"[Docker] Tagging {localImageTag}:latest as {fullUri}");
         await RunProcessAsync("docker", $"tag {localImageTag}:latest {fullUri}", ct: ct);
-        Console.Error.WriteLine($"[Docker] Pushing {fullUri}");
-        await RunProcessAsync("docker", $"{configFlag} push {fullUri}", ct: ct);
-        Console.Error.WriteLine($"[Docker] Push complete: {fullUri}");
+
+        // Push with retry — ECR pushes can fail with transient TCP resets
+        for (var attempt = 1; attempt <= 3; attempt++)
+        {
+            try
+            {
+                Console.Error.WriteLine($"[Docker] Pushing {fullUri} (attempt {attempt})");
+                await RunProcessAsync("docker", $"{configFlag} push {fullUri}", ct: ct);
+                Console.Error.WriteLine($"[Docker] Push complete: {fullUri}");
+                break;
+            }
+            catch (Exception ex) when (attempt < 3)
+            {
+                Console.Error.WriteLine($"[Docker] Push attempt {attempt} failed: {ex.Message}. Retrying in 5s...");
+                await Task.Delay(TimeSpan.FromSeconds(5), ct);
+            }
+        }
 
         return fullUri;
     }

test/AWS.AgentCore.IntegrationTests/Infrastructure/inttest-stack.template.json

@@ -118,6 +118,12 @@
                   "Resource": {
                     "Fn::Sub": "arn:aws:logs:${AWS::Region}:${AWS::AccountId}:*"
                   }
+                },
+                {
+                  "Sid": "S3ListBuckets",
+                  "Effect": "Allow",
+                  "Action": ["s3:ListAllMyBuckets"],
+                  "Resource": "*"
                 }
               ]
             }

test/AWS.AgentCore.IntegrationTests/NonStreamingAgentTests.cs

@@ -102,6 +102,22 @@ public async Task Invoke_AppInfoReportsNotNativeAot()
         Assert.Contains("\"isNativeAot\":false", result.Message.Replace(" ", ""), StringComparison.OrdinalIgnoreCase);
     }
 
+    [Fact]
+    public async Task Invoke_S3BucketCountReturnsNumber()
+    {
+        var ct = TestContext.Current.CancellationToken;
+        var result = await _invoker.InvokeAsync(
+            _fixture.RuntimeArn,
+            "Call the GetS3BucketCount tool and respond with ONLY the exact JSON it returns. Do not add any other text.",
+            ct);
+
+        Assert.Equal(200, result.HttpStatusCode);
+        // The tool must successfully call S3 — meaning credentials resolved correctly.
+        // If credentials fail, the tool returns {"error":"...", "message":"..."} instead.
+        Assert.Contains("bucketCount", result.Message, StringComparison.OrdinalIgnoreCase);
+        Assert.DoesNotContain("error", result.Message, StringComparison.OrdinalIgnoreCase);
+    }
+
     public void Dispose() => _invoker.Dispose();
 }