feat: Add Vertex provider

src/Cellm/AddIn/CellmAddIn.cs

@@ -16,6 +16,7 @@
 using Cellm.Models.Providers.OpenAi;
 using Cellm.Models.Providers.OpenAiCompatible;
 using Cellm.Models.Providers.OpenRouter;
+using Cellm.Models.Providers.Vertex;
 using Cellm.Models.Resilience;
 using Cellm.Tools;
 using Cellm.Tools.FileReader;
@@ -84,6 +85,7 @@ private static ServiceCollection ConfigureServices(ServiceCollection services)
             .Configure<OllamaConfiguration>(configuration.GetRequiredSection(nameof(OllamaConfiguration)))
             .Configure<OpenAiConfiguration>(configuration.GetRequiredSection(nameof(OpenAiConfiguration)))
             .Configure<OpenAiCompatibleConfiguration>(configuration.GetRequiredSection(nameof(OpenAiCompatibleConfiguration)))
+            .Configure<VertexConfiguration>(configuration.GetRequiredSection(nameof(VertexConfiguration)))
             .Configure<OpenRouterConfiguration>(configuration.GetRequiredSection(nameof(OpenRouterConfiguration)))
             .Configure<ResilienceConfiguration>(configuration.GetRequiredSection(nameof(ResilienceConfiguration)))
             .Configure<SentryConfiguration>(configuration.GetRequiredSection(nameof(SentryConfiguration)));
@@ -149,7 +151,7 @@ private static ServiceCollection ConfigureServices(ServiceCollection services)
                 cfg.AddBehavior<UsageBehavior<ProviderRequest, ProviderResponse>>(ServiceLifetime.Singleton);
             })
             .AddSingleton<IProviderBehavior, AdditionalPropertiesBehavior>()
-            .AddSingleton<IProviderBehavior, GeminiTemperatureBehavior>()
+            .AddSingleton<IProviderBehavior, GoogleTemperatureBehavior>()
             .AddSingleton<IProviderBehavior, OpenAiTemperatureBehavior>()
             .AddSingleton<IProviderBehavior, MistralThinkingBehavior>();
 
@@ -169,6 +171,7 @@ private static ServiceCollection ConfigureServices(ServiceCollection services)
             .AddResilientHttpClient(resilienceConfiguration, cellmAddInConfiguration, Provider.Gemini)
             .AddResilientHttpClient(resilienceConfiguration, cellmAddInConfiguration, Provider.Mistral)
             .AddResilientHttpClient(resilienceConfiguration, cellmAddInConfiguration, Provider.OpenAiCompatible)
+            .AddResilientHttpClient(resilienceConfiguration, cellmAddInConfiguration, Provider.Vertex)
             .AddResilientHttpClient(resilienceConfiguration, cellmAddInConfiguration, Provider.OpenRouter);
 
 #pragma warning disable EXTEXP0018 // Type is for evaluation purposes only and is subject to change or removal in future updates.
@@ -189,6 +192,7 @@ private static ServiceCollection ConfigureServices(ServiceCollection services)
             .AddOllamaChatClient()
             .AddOpenAiChatClient()
             .AddOpenAiCompatibleChatClient()
+            .AddVertexChatClient()
             .AddOpenRouterChatClient();
 
         // Add tools
@@ -237,6 +241,7 @@ internal static IEnumerable<IProviderConfiguration> GetProviderConfigurations()
             Services.GetRequiredService<IOptionsMonitor<OllamaConfiguration>>().CurrentValue,
             Services.GetRequiredService<IOptionsMonitor<OpenAiConfiguration>>().CurrentValue,
             Services.GetRequiredService<IOptionsMonitor<OpenAiCompatibleConfiguration>>().CurrentValue,
+            Services.GetRequiredService<IOptionsMonitor<VertexConfiguration>>().CurrentValue,
             Services.GetRequiredService<IOptionsMonitor<OpenRouterConfiguration>>().CurrentValue
         ];
     }

src/Cellm/AddIn/UserInterface/Ribbon/RibbonModelGroup.cs

@@ -12,6 +12,7 @@
 using Cellm.Models.Providers.Ollama;
 using Cellm.Models.Providers.OpenAi;
 using Cellm.Models.Providers.OpenAiCompatible;
+using Cellm.Models.Providers.Vertex;
 using Cellm.Models.Providers.OpenRouter;
 using Cellm.Users;
 using ExcelDna.Integration.CustomUI;
@@ -495,6 +496,8 @@
                 case Provider.OpenAiCompatible:
                     currentBaseAddress = GetProviderConfiguration<OpenAiCompatibleConfiguration>()?.BaseAddress?.ToString() ?? "";
                     break;
+                case Provider.Vertex:
+                    currentBaseAddress = GetProviderConfiguration<VertexConfiguration>()?.BaseAddress?.ToString() ?? "";
                 case Provider.OpenRouter:
                     currentBaseAddress = GetProviderConfiguration<OpenRouterConfiguration>()?.BaseAddress?.ToString() ?? "";
                     break;
@@ -551,7 +554,7 @@
     {
         return provider switch
         {
-            Provider.Azure or Provider.Aws or Provider.OpenAiCompatible => true,
+            Provider.Azure or Provider.Aws or Provider.OpenAiCompatible or Provider.Vertex => true,
             _ => false
         };
     }

src/Cellm/Cellm.csproj

@@ -92,5 +92,6 @@
     <EmbeddedResource Include="AddIn\UserInterface\Resources\Ollama.png" />
     <EmbeddedResource Include="AddIn\UserInterface\Resources\OpenAi.png" />
     <EmbeddedResource Include="AddIn\UserInterface\Resources\OpenRouter.svg" />
+    <EmbeddedResource Include="AddIn\UserInterface\Resources\Vertex.png" />
   </ItemGroup>
 </Project>

src/Cellm/Models/Providers/Behaviors/GeminiTemperatureBehavior.cs → src/Cellm/Models/Providers/Behaviors/GoogleTemperatureBehavior.cs

@@ -4,24 +4,24 @@
 
 namespace Cellm.Models.Providers.Behaviors;
 
-internal class GeminiTemperatureBehavior(IOptionsMonitor<CellmAddInConfiguration> cellmAddinConfiguration) : IProviderBehavior
+internal class GoogleTemperatureBehavior(IOptionsMonitor<CellmAddInConfiguration> cellmAddinConfiguration) : IProviderBehavior
 {
     private const float DefaultMinTemp = 0.0f;
     private const float DefaultMaxTemp = 1.0f;
-    private const float GeminiMaxTemperature = 2.0f;
+    private const float GoogleMaxTemperature = 2.0f;
 
     public bool IsEnabled(Provider provider)
     {
-        return provider == Provider.Gemini;
+        return provider == Provider.Gemini || provider == Provider.Vertex;
     }
 
     public void Before(Provider provider, Prompt prompt)
     {
         var temperature = prompt.Options.Temperature ?? (float)cellmAddinConfiguration.CurrentValue.DefaultTemperature;
 
         // Scale temperature from [0;1] to [0;2]
-        temperature = (temperature / DefaultMaxTemp) * GeminiMaxTemperature;
-        prompt.Options.Temperature = Math.Clamp(temperature, DefaultMinTemp, GeminiMaxTemperature);
+        temperature = (temperature / DefaultMaxTemp) * GoogleMaxTemperature;
+        prompt.Options.Temperature = Math.Clamp(temperature, DefaultMinTemp, GoogleMaxTemperature);
     }
 
     public void After(Provider Provider, Prompt prompt)
@@ -31,7 +31,7 @@ public void After(Provider Provider, Prompt prompt)
             var temperature = prompt.Options.Temperature.Value;
 
             // Scale temperature back from [0;2] to [0;1]
-            temperature = (temperature / GeminiMaxTemperature) * DefaultMaxTemp;
+            temperature = (temperature / GoogleMaxTemperature) * DefaultMaxTemp;
             prompt.Options.Temperature = Math.Clamp(temperature, DefaultMinTemp, DefaultMaxTemp);
         }
     }

src/Cellm/Models/Providers/Provider.cs

@@ -12,5 +12,6 @@ public enum Provider
     Ollama,
     OpenAi,
     OpenAiCompatible,
-    OpenRouter
+    OpenRouter,
+    Vertex
 }

src/Cellm/Models/Providers/Vertex/VertexConfiguration.cs

@@ -0,0 +1,35 @@
+using Cellm.Users;
+using Microsoft.Extensions.AI;
+
+namespace Cellm.Models.Providers.Vertex;
+
+internal class VertexConfiguration : IProviderConfiguration
+{
+    public Provider Id { get => Provider.Vertex; }
+
+    public string Name { get => "Vertex AI"; }
+
+    public Entitlement Entitlement { get => Entitlement.EnableVertexProvider; }
+
+    public string Icon { get => $"AddIn/UserInterface/Resources/{nameof(Provider.Vertex)}.png"; }
+
+    public Uri BaseAddress { get; init; } = new Uri("https://us-central1-aiplatform.googleapis.com/v1beta1/projects/YOUR_PROJECT_ID/locations/us-central1/endpoints/openapi");
+
+    public string DefaultModel { get; init; } = string.Empty;
+
+    public string ApiKey { get; init; } = string.Empty;
+
+    public string SmallModel { get; init; } = string.Empty;
+
+    public string MediumModel { get; init; } = string.Empty;
+
+    public string LargeModel { get; init; } = string.Empty;
+
+    public AdditionalPropertiesDictionary? AdditionalProperties { get; init; } = [];
+
+    public bool SupportsJsonSchemaResponses { get; init; } = true;
+
+    public bool SupportsStructuredOutputWithTools { get; init; } = false;
+
+    public bool IsEnabled { get; init; } = false;
+}

src/Cellm/Models/ServiceCollectionExtensions.cs

@@ -22,6 +22,7 @@
 using Cellm.Models.Providers.OpenAi;
 using Cellm.Models.Providers.OpenAiCompatible;
 using Cellm.Models.Providers.OpenRouter;
+using Cellm.Models.Providers.Vertex;
 using Cellm.Models.Resilience;
 using Cellm.Users;
 using Microsoft.Extensions.AI;
@@ -427,6 +428,34 @@
         return services;
     }
 
+    public static IServiceCollection AddVertexChatClient(this IServiceCollection services)
+    {
+        services
+            .AddKeyedChatClient(Provider.Vertex, serviceProvider =>
+            {
+                var account = serviceProvider.GetRequiredService<Account>();
+                account.ThrowIfNotEntitled(Entitlement.EnableVertexProvider);
+
+                var vertexConfiguration = serviceProvider.GetRequiredService<IOptionsMonitor<VertexConfiguration>>();
+                var resilientHttpClient = serviceProvider.GetResilientHttpClient(Provider.Vertex);
+
+                if (string.IsNullOrWhiteSpace(vertexConfiguration.CurrentValue.ApiKey))
+                {
+                    throw new CellmException($"Empty {nameof(VertexConfiguration.ApiKey)} for {Provider.Vertex}. Please set your API key.");
+                }
+
+                var openAiClient = new OpenAIClient(
+                    new ApiKeyCredential(vertexConfiguration.CurrentValue.ApiKey),
+                    new OpenAIClientOptions
+                    {
+                        Transport = new HttpClientPipelineTransport(resilientHttpClient),
+                        Endpoint = vertexConfiguration.CurrentValue.BaseAddress
+                    });
+
+                return openAiClient.GetChatClient(vertexConfiguration.CurrentValue.DefaultModel).AsIChatClient();
+            });
+    }
+
     public static IServiceCollection AddOpenRouterChatClient(this IServiceCollection services)
     {
         services

src/Cellm/Users/Entitlement.cs

@@ -15,6 +15,7 @@ public enum Entitlement
     EnableOpenAiCompatibleProviderLocalModels,
     EnableOpenAiCompatibleProviderHostedModels,
     EnableOpenRouterProvider,
+    EnableVertexProvider,
     EnableModelContextProtocol,
     DisableTelemetry
 }

src/Cellm/Users/Models/Entitlements.cs

@@ -19,6 +19,7 @@ internal class Entitlements()
         Entitlement.EnableDeepSeekProvider,
         Entitlement.EnableGeminiProvider,
         Entitlement.EnableMistralProvider,
+        Entitlement.EnableModelContextProtocol,
         Entitlement.EnableOllamaProvider,
         Entitlement.EnableOpenAiProvider,
         Entitlement.EnableOpenAiCompatibleProvider,

src/Cellm/appsettings.json

@@ -110,6 +110,14 @@
         "LargeModel": "anthropic/claude-opus-4-5-20251101",
         "IsEnabled": true
     },
+    "VertexConfiguration": {
+        "BaseAddress": "https://us-central1-aiplatform.googleapis.com/v1beta1/projects/YOUR_PROJECT_ID/locations/us-central1/endpoints/openapi",
+        "DefaultModel": "gemini-2.5-flash",
+        "ApiKey": "",
+        "SmallModel": "gemini-2.5-flash-lite",
+        "MediumModel": "gemini-2.5-flash",
+        "LargeModel": "gemini-2.5-pro",
+    },
     "ModelContextProtocolConfiguration": {
         "StdioServers": [
             {