Mismatched dependency version when using Google.Cloud.VertexAI.Extensions

#### Environment details - OS: macOS 26.2 - .NET version: .NET SDK 10.0.101 - Package name and version: Google.Cloud.VertexAI.Extensions version 1.0.0-beta02 #### Steps to reproduce 1. `dotnet new console` 2. `dotnet add package Google.Cloud.VertexAI.Extensions --version 1.0.0-beta02` 3. Set the contents of `Program.cs` to the following: ```csharp using Microsoft.Extensions.AI; using System; var chatClient = CreateVertexAiChatClient(); await foreach (var message in chatClient.GetStreamingResponseAsync(new ChatMessage(ChatRole.User, "Say 'hi'."))) { Console.Write(message.Text); } static IChatClient CreateVertexAiChatClient() { const string GCP_PROJECT_ID = "!!!!!! YOUR PROJECT ID GOES HERE !!!!!!"; const string GCP_REGION = "us-central1"; var builder = new Google.Cloud.AIPlatform.V1.PredictionServiceClientBuilder() { Endpoint = $"https://{GCP_REGION}-aiplatform.googleapis.com", QuotaProject = GCP_PROJECT_ID, }; string model = $"projects/{GCP_PROJECT_ID}/locations/{GCP_REGION}/publishers/google/models/gemini-2.5-flash-lite"; return Google.Cloud.VertexAI.Extensions.VertexAIExtensions.BuildIChatClient(builder, defaultModelId: model); } ``` #### Expected Result Prints the output of the LLM. #### Actual Result An error occurs: ``` System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.Bcl.AsyncInterfaces, Version=10.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. The system cannot find the file specified. File name: 'Microsoft.Bcl.AsyncInterfaces, Version=10.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' at Google.Cloud.VertexAI.Extensions.VertexAIExtensions.BuildIChatClient(PredictionServiceClientBuilder builder, String defaultModelId, IServiceProvider provider) at Program.<<Main>$>g__CreateVertexAiChatClient|0_0() in /Users/austin/src/test-vertex-ai-extenstions/Program.cs:line 22 at Program.<Main>$(String[] args) in /Users/austin/src/test-vertex-ai-extenstions/Program.cs:line 4 at Program.<Main>(String[] args) ``` #### Workaround Directly reference the `Microsoft.Bcl.AsyncInterfaces` Nuget package: ``` dotnet add package Microsoft.Bcl.AsyncInterfaces --version 10.0.1 ``` #### Analysis The `Google.Cloud.VertexAI.Extensions` Nuget package [declares](https://www.nuget.org/packages/Google.Cloud.VertexAI.Extensions/1.0.0-beta02#dependencies-body-tab) dependencies on two packages (`Google.Cloud.AIPlatform.V1` and `Microsoft.Extensions.AI.Abstractions`). When the package is restored, version 6.0.0 of `Microsoft.Bcl.AsyncInterfaces` is restored. According to the `project.assets.json` file, this version of the dependency is installed because package `Google.Api.Gax` version 4.12.1 depends on it. However the .NET Standard version of `Google.Cloud.VertexAI.Extensions.dll` depends on version 10.0.0 of the `Microsoft.Bcl.AsyncInterfaces` assembly. To fix this problem, I think the `Google.Cloud.VertexAI.Extensions` Nuget package should declare a dependency on `Microsoft.Bcl.AsyncInterfaces` so that it gets a compatible version. Note that this is not the only undeclared dependency of the `Google.Cloud.VertexAI.Extensions` package. It may be worthwhile adding explicit dependencies on some of the other direct packages to prevent similar issues. Here are all the dependancies of `Google.Cloud.VertexAI.Extensions.dll`. | Assembly | Version | | -- | -- | | Google.Api.Gax | 4.12.1.0 | | Google.Api.Gax.Grpc | 4.12.1.0 | | Google.Apis.Auth | 1.72.0.0 | | Google.Cloud.AIPlatform.V1 | 3.54.0.0 | | Google.Protobuf | 3.31.1.0 | | Grpc.Core.Api | 2.0.0.0 | | Microsoft.Bcl.AsyncInterfaces | 10.0.0.0 | | Microsoft.Extensions.AI.Abstractions | 10.0.0.0 | | Microsoft.Extensions.Logging.Abstractions | 6.0.0.0 | | netstandard | 2.0.0.0 | | System.Memory | 4.0.2.0 | | System.Text.Json | 10.0.0.0 | | System.Threading.Tasks.Extensions | 4.2.1.0 |