Gemini API Key is not being passed Correctly

[TheLinuxMaster]

Describe the bug

I'm trying to send a simple request, but every time i execute the code, the key is always empty. also there is virtually no documentation on gemini provider

 public async Task<string> Chat(ChatRequest request)
        {
            string messsage = "";
            using (var client = new HttpClient())
            {
                GoogleConfiguration config = new()
                {
                    ApiKey = ""
                };
                GoogleProvider provider = new(config, client);

                GoogleChatModel model = new(provider, "gemini-2.0-flash");

                StringBuilder sb = new StringBuilder();

                await foreach (var response in model.GenerateAsync("What is the meaning of life"))
                {
                    sb.Append(response);
                }

                messsage = sb.ToString();
            }

            return messsage;
        }

but the response i get is this:

GenerativeAI.Exceptions.GenerativeAIException: Error while requesting https://generativelanguage.googleapis.com/v1beta/models/gemini-2.0-flash:generateContent?key=__API_Key__:

{
  "error": {
    "code": 403,
    "message": "Method doesn't allow unregistered callers (callers without established identity). Please use API Key or other form of API consumer identity to call this API.",
    "status": "PERMISSION_DENIED"
  }
}

   at GenerativeAI.Models.ModelBase.GenerateContent(String apiKey, String model, GenerateContentRequest request) in D:\GitHub\Google_GenerativeAI\src\GenerativeAI\Models\ModelBase.cs:line 68
   at GenerativeAI.Models.GenerativeModel.GenerateContentAsync(GenerateContentRequest request, CancellationToken cancellationToken) in D:\GitHub\Google_GenerativeAI\src\GenerativeAI\Models\GenerativeModel.cs:line 157
   at LangChain.Providers.Google.GoogleChatModel.CreateChatCompletionAsync(IReadOnlyCollection`1 messages, CancellationToken cancellationToken) in /_/src/Google/src/GoogleChatModel.cs:line 89
   at LangChain.Providers.Google.GoogleChatModel.GenerateAsync(ChatRequest request, ChatSettings settings, CancellationToken cancellationToken)+MoveNext() in /_/src/Google/src/GoogleChatModel.cs:line 151
   at LangChain.Providers.Google.GoogleChatModel.GenerateAsync(ChatRequest request, ChatSettings settings, CancellationToken cancellationToken)+System.Threading.Tasks.Sources.IValueTaskSource<System.Boolean>.GetResult()
   at BotTalk.Services.Implementation.WhatsAppService.Chat(ChatRequest request) in D:\BotTalk\BotTalk\Services\Implementation\WhatsAppService.cs:line 40
   at BotTalk.Services.Implementation.WhatsAppService.Chat(ChatRequest request) in D:\BotTalk\BotTalk\Services\Implementation\WhatsAppService.cs:line 40
   at BotTalk.Controllers.WhatsAppController.Get(ChatRequest request) in D:\BotTalk\BotTalk\Controllers\WhatsAppController.cs:line 25
   at lambda_method5(Closure, Object)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.AwaitableObjectResultExecutor.Execute(ActionContext actionContext, IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeActionMethodAsync>g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeNextActionFilterAsync>g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeInnerFilterAsync>g__Awaited|13_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
   at Swashbuckle.AspNetCore.SwaggerUI.SwaggerUIMiddleware.Invoke(HttpContext httpContext)
   at Swashbuckle.AspNetCore.Swagger.SwaggerMiddleware.Invoke(HttpContext httpContext, ISwaggerProvider swaggerProvider)
   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddlewareImpl.Invoke(HttpContext context)

HEADERS
=======
Accept: text/plain
Host: localhost:7248
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36 Edg/135.0.0.0
Accept-Encoding: gzip, deflate, br, zstd
Accept-Language: en-US,en;q=0.9
Content-Type: application/json
Origin: https://localhost:7248
Referer: https://localhost:7248/swagger/index.html
Content-Length: 60
sec-ch-ua-platform: "Windows"
sec-ch-ua: "Microsoft Edge";v="135", "Not-A.Brand";v="8", "Chromium";v="135"
sec-ch-ua-mobile: ?0
sec-fetch-site: same-origin
sec-fetch-mode: cors
sec-fetch-dest: empty
priority: u=1, i

Steps to reproduce the bug

replace the api key and execute the code.

public async Task<string> Chat(ChatRequest request)
        {
            string messsage = "";
            using (var client = new HttpClient())
            {
                GoogleConfiguration config = new()
                {
                    ApiKey = ""
                };
                GoogleProvider provider = new(config, client);

                GoogleChatModel model = new(provider, "gemini-2.0-flash");

                StringBuilder sb = new StringBuilder();

                await foreach (var response in model.GenerateAsync("What is the meaning of life"))
                {
                    sb.Append(response);
                }

                messsage = sb.ToString();
            }

            return messsage;
        }

Expected behavior

No response

Screenshots

No response

NuGet package version

No response

Additional context

No response