diff --git a/aspnetcore/fundamentals/openapi/using-openapi-documents.md b/aspnetcore/fundamentals/openapi/using-openapi-documents.md
index b07ab2643cba..9a497eec58fb 100644
--- a/aspnetcore/fundamentals/openapi/using-openapi-documents.md
+++ b/aspnetcore/fundamentals/openapi/using-openapi-documents.md
@@ -109,21 +109,22 @@ public class DocumentService
 {
     private readonly IOpenApiDocumentProvider _documentProvider;
 
-    public DocumentService(IOpenApiDocumentProvider documentProvider)
+    public DocumentService([FromKeyedServices("v1")] IOpenApiDocumentProvider documentProvider)
     {
         _documentProvider = documentProvider;
     }
 
-    public async Task<OpenApiDocument> GetApiDocumentAsync()
+    public Task<OpenApiDocument> GetApiDocumentAsync(CancellationToken cancellationToken = default)
     {
-        return await _documentProvider.GetOpenApiDocumentAsync("v1");
+        return _documentProvider.GetOpenApiDocumentAsync(cancellationToken);
     }
 }
 ```
 
-Register the service in your DI container:
+Register the service in your DI container. Note that service key "v1" should match the document name passed to `AddOpenApi`:
 
 ```csharp
+builder.Services.AddOpenApi("v1");
 builder.Services.AddScoped<DocumentService>();
 ```