Set default OutputPath and add IntermediateOutputPath at PipelineContext level

src/Aspire.Hosting.Azure/AzureEnvironmentResource.cs

@@ -225,7 +225,7 @@ private Task PublishAsync(PipelineStepContext context)
         var azureProvisioningOptions = context.Services.GetRequiredService<IOptions<AzureProvisioningOptions>>();
         var activityReporter = context.PipelineContext.Services.GetRequiredService<IPipelineActivityReporter>();
         var publishingContext = new AzurePublishingContext(
-            context.OutputPath ?? throw new InvalidOperationException("OutputPath is required for Azure publishing."),
+            context.OutputPath,
             azureProvisioningOptions.Value,
             context.Services,
             context.Logger,

src/Aspire.Hosting.Docker/DockerComposePublishingContext.cs

@@ -36,7 +36,7 @@ internal sealed class DockerComposePublishingContext(
         UnixFileMode.OtherRead | UnixFileMode.OtherWrite;
 
     public readonly IResourceContainerImageBuilder ImageBuilder = imageBuilder;
-    public readonly string OutputPath = outputPath ?? throw new InvalidOperationException("OutputPath is required for Docker Compose publishing.");
+    public readonly string OutputPath = outputPath;
 
     internal async Task WriteModelAsync(DistributedApplicationModel model, DockerComposeEnvironmentResource environment)
     {

src/Aspire.Hosting.Kubernetes/KubernetesPublishingContext.cs

@@ -20,7 +20,7 @@ internal sealed class KubernetesPublishingContext(
     ILogger logger,
     CancellationToken cancellationToken = default)
 {
-    public readonly string OutputPath = outputPath ?? throw new InvalidOperationException("OutputPath is required for Kubernetes publishing.");
+    public readonly string OutputPath = outputPath;
 
     private readonly Dictionary<string, Dictionary<string, object>> _helmValues = new()
     {

src/Aspire.Hosting/Pipelines/PipelineContext.cs

@@ -3,6 +3,8 @@
 
 using System.Diagnostics.CodeAnalysis;
 using Aspire.Hosting.ApplicationModel;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 
 namespace Aspire.Hosting.Pipelines;
@@ -53,5 +55,24 @@ public sealed class PipelineContext(
     /// <summary>
     /// Gets the output path for deployment artifacts.
     /// </summary>
-    public string? OutputPath { get; } = outputPath;
+    public string OutputPath { get; } = outputPath ?? Path.Combine(Environment.CurrentDirectory, "aspire-output");
+
+    /// <summary>
+    /// Gets the intermediate output path for temporary build artifacts.
+    /// </summary>
+    public string IntermediateOutputPath { get; } = GetIntermediateOutputPath(serviceProvider);
+
+    private static string GetIntermediateOutputPath(IServiceProvider serviceProvider)
+    {
+        var configuration = serviceProvider.GetRequiredService<IConfiguration>();
+        var appHostSha = configuration["AppHost:PathSha256"];
+
+        if (!string.IsNullOrEmpty(appHostSha))
+        {
+            return Path.Combine(Path.GetTempPath(), "aspire", appHostSha);
+        }
+
+        // Fallback if AppHost:PathSha256 is not available
+        return Path.Combine(Path.GetTempPath(), "aspire", Guid.NewGuid().ToString("N"));
+    }
 }

src/Aspire.Hosting/Pipelines/PipelineStepContext.cs

@@ -62,7 +62,12 @@ public sealed class PipelineStepContext
     /// <summary>
     /// Gets the output path for deployment artifacts.
     /// </summary>
-    public string? OutputPath => PipelineContext.OutputPath;
+    public string OutputPath => PipelineContext.OutputPath;
+
+    /// <summary>
+    /// Gets the intermediate output path for temporary build artifacts.
+    /// </summary>
+    public string IntermediateOutputPath => PipelineContext.IntermediateOutputPath;
 }
 
 /// <summary>

src/Shared/PublishingContextUtils.cs

@@ -16,10 +16,10 @@ public static string GetEnvironmentOutputPath(PipelineStepContext context, IComp
         if (context.Model.Resources.OfType<IComputeEnvironmentResource>().Count() > 1)
         {
             // If there are multiple compute environments, append the environment name to the output path
-            return Path.Combine(context.OutputPath!, environment.Name);
+            return Path.Combine(context.OutputPath, environment.Name);
         }
 
         // If there is only one compute environment, use the root output path
-        return context.OutputPath!;
+        return context.OutputPath;
     }
 }