Refactor models, update usage tracking, and clean citations

- Enabled additional C# code style suggestions in .editorconfig.
- Removed citation rendering and extraction from Ask.razor.
- Deleted Citation, ChatResponse, and TokenUsage models and references.
- Updated TokenUsageResponse to use UsageDetails from Microsoft.Extensions.AI.
- Refactored Response model: removed citations, added ConversationId, and adopted new token usage structure.
- Updated HybridCacheSessionStoreService with new cache key format and DeleteSessionAsync method.
- Refactored VectorSearchService to remove AppSettings dependency, update method signatures, and use UsageDetails for token tracking.
- Updated NuGet package references in SqlDatabaseVectorSearch.csproj.

.editorconfig

@@ -124,6 +124,7 @@ csharp_style_prefer_null_check_over_type_check = true:suggestion
 
 # Modifier preferences
 csharp_prefer_static_local_function = true:suggestion
+csharp_prefer_static_anonymous_function = true:suggestion
 csharp_preferred_modifier_order = public,private,protected,internal,static,extern,new,virtual,abstract,sealed,override,readonly,unsafe,volatile,async:silent
 
 # Code-block preferences
@@ -139,9 +140,11 @@ csharp_prefer_system_threading_lock = true:suggestion
 csharp_prefer_simple_default_expression = true:suggestion
 csharp_style_deconstructed_variable_declaration = false:suggestion
 csharp_style_inlined_variable_declaration = true:suggestion
+csharp_style_prefer_implicitly_typed_lambda_expression = true:suggestion
 csharp_style_pattern_local_over_anonymous_function = true:suggestion
 csharp_style_prefer_index_operator = true:suggestion
 csharp_style_prefer_range_operator = true:suggestion
+csharp_style_prefer_unbound_generic_type_in_nameof = true:suggestion
 csharp_style_throw_expression = true:suggestion
 csharp_style_unused_value_assignment_preference = discard_variable:none
 csharp_style_unused_value_expression_statement_preference = discard_variable:none

SqlDatabaseVectorSearch/Components/Pages/Ask.razor

@@ -83,23 +83,6 @@
                                                 </Tooltip>
                                             </div>
                                         </div>
-                                        @if (message.Citations is not null && message.Citations.Count() > 0)
-                                        {
-                                            <div class="mt-3 d-flex flex-wrap">
-                                                @foreach (var citation in message.Citations)
-                                                {
-                                                    <div class="border rounded p-2 me-2 mb-2 citation-box small">
-                                                        <div>
-                                                            <strong>@citation.FileName</strong> @if (citation.PageNumber.GetValueOrDefault() > 0)
-                                                            {
-                                                                <span class="ms-2">pag. @citation.PageNumber</span>
-                                                            }
-                                                        </div>
-                                                        <div class="text-secondary small mt-1">@citation.Quote</div>
-                                                    </div>
-                                                }
-                                            </div>
-                                        }
                                     }
                                 </div>
                             }
@@ -212,17 +195,6 @@
                 }
                 else if (delta.StreamState == StreamState.End)
                 {
-                    // Get citations from the response.
-                    assistantMessage.Citations = delta.Citations?.Select(c => new Citation
-                    {
-                        DocumentId = c.DocumentId,
-                        ChunkId = c.ChunkId,
-                        FileName = c.FileName,
-                        Quote = c.Quote,
-                        PageNumber = c.PageNumber,
-                        IndexOnPage = c.IndexOnPage
-                    });
-
                     assistantMessage.Status = MessageStatus.Completed;
                     assistantMessage.TokenUsage += FormatTokenUsage(delta.TokenUsage);
                 }
@@ -282,26 +254,22 @@
             ? $"<p><strong>Reformulation:</strong><br />{FormatTokenUsageDetails(tokenUsageResponse.Reformulation)}</p>"
             : string.Empty;
 
-        var embeddingTokenCount = tokenUsageResponse.EmbeddingTokenCount.HasValue
-            ? $"<p><strong>Embedding Token Count:</strong> {tokenUsageResponse.EmbeddingTokenCount}</p>"
-            : string.Empty;
-
         var question = tokenUsageResponse.Question is not null
             ? $"<p><strong>Question:</strong><br />{FormatTokenUsageDetails(tokenUsageResponse.Question)}</p>"
             : string.Empty;
 
-        return $"{reformulation}{embeddingTokenCount}{question}";
+        return $"{reformulation}{question}";
 
-        static string FormatTokenUsageDetails(TokenUsage? tokenUsage)
+        static string FormatTokenUsageDetails(Microsoft.Extensions.AI.UsageDetails? tokenUsage)
         {
             if (tokenUsage is null)
             {
                 return string.Empty;
             }
 
-            return $"Prompt tokens: {tokenUsage.PromptTokens}<br />" +
+            return $"Input tokens: {tokenUsage.InputTokenCount}<br />" +
-                   $"Completion tokens: {tokenUsage.CompletionTokens}<br />" +
+                   $"Output tokens: {tokenUsage.OutputTokenCount}<br />" +
-                   $"Total tokens: {tokenUsage.TotalTokens}";
+                   $"Total tokens: {tokenUsage.TotalTokenCount}";
         }
     }
 
@@ -326,23 +294,5 @@
         public MessageStatus Status { get; set; } = MessageStatus.New;
 
         public string? TokenUsage { get; set; }
-
-        // List of citations extracted from the answer.
-        public IEnumerable<Citation>? Citations { get; set; }
-    }
-
-    public class Citation
-    {
-        public Guid DocumentId { get; set; }
-
-        public Guid ChunkId { get; set; }
-
-        public string FileName { get; set; } = null!;
-
-        public string Quote { get; set; } = null!;
-
-        public int? PageNumber { get; set; }
-
-        public int IndexOnPage { get; set; }
     }
 }

SqlDatabaseVectorSearch/Models/ChatResponse.cs

@@ -1,3 +0,0 @@
-namespace SqlDatabaseVectorSearch.Models;
-
-public record class ChatResponse(string? Text, TokenUsage? TokenUsage = null);

SqlDatabaseVectorSearch/Models/Citation.cs

@@ -1,16 +0,0 @@
-namespace SqlDatabaseVectorSearch.Models;
-
-public class Citation
-{
-    public Guid DocumentId { get; set; }
-
-    public Guid ChunkId { get; set; }
-
-    public string FileName { get; set; } = null!;
-
-    public string Quote { get; set; } = null!;
-
-    public int? PageNumber { get; set; }
-
-    public int IndexOnPage { get; set; }
-}

SqlDatabaseVectorSearch/Models/Response.cs

@@ -1,12 +1,10 @@
 namespace SqlDatabaseVectorSearch.Models;
 
 // Question and Answer can be null when using response streaming.
-public record class Response(string? OriginalQuestion, string? ReformulatedQuestion, string? Answer, StreamState? StreamState = null, TokenUsageResponse? TokenUsage = null, IEnumerable<Citation>? Citations = null)
+public record class Response(Guid ConversationId, string? OriginalQuestion, string? ReformulatedQuestion, string? Answer, StreamState? StreamState = null, TokenUsageResponse? TokenUsage = null)
 {
-    public Response(string? token, StreamState streamState, TokenUsageResponse? tokenUsageResponse = null, IEnumerable<Citation>? citations = null)
+    public Response(Guid conversationId, string? token, StreamState streamState, TokenUsageResponse? tokenUsageResponse = null)
-        : this(null, null, token, streamState, tokenUsageResponse, citations)
+        : this(conversationId, null, null, token, streamState, tokenUsageResponse)
     {
     }
 }
-
-public record class RagResponse(Guid ConversationId, string OriginalQuestion, string ReformulatedQuestion, string Answer);

SqlDatabaseVectorSearch/Models/TokenUsage.cs

@@ -1,6 +0,0 @@
-namespace SqlDatabaseVectorSearch.Models;
-
-public record class TokenUsage(int PromptTokens, int CompletionTokens)
-{
-    public int TotalTokens => PromptTokens + CompletionTokens;
-}

SqlDatabaseVectorSearch/Models/TokenUsageResponse.cs

@@ -1,9 +1,5 @@
-namespace SqlDatabaseVectorSearch.Models;
+using Microsoft.Extensions.AI;
 
-public record class TokenUsageResponse(TokenUsage? Reformulation, int? EmbeddingTokenCount, TokenUsage? Question)
+namespace SqlDatabaseVectorSearch.Models;
-{
+
-    public TokenUsageResponse(TokenUsage? question)
+public record class TokenUsageResponse(UsageDetails? Reformulation, UsageDetails? Question);
-        : this(null, null, question)
-    {
-    }
-}

SqlDatabaseVectorSearch/Services/HybridCacheSessionStoreService.cs

@@ -8,23 +8,30 @@ public class HybridCacheSessionStoreService(HybridCache cache) : AgentSessionSto
 {
     public override async ValueTask<AgentSession> GetSessionAsync(AIAgent agent, string conversationId, CancellationToken cancellationToken = default)
     {
-        var sessionContent = await cache.GetOrCreateAsync(
+        var key = GetKey(agent, conversationId);
-            GetCacheKey(conversationId),
+        var sessionContent = await cache.GetOrCreateAsync(key, async ct =>
-            async ct =>
         {
             var session = await agent.CreateSessionAsync(ct);
             return await agent.SerializeSessionAsync(session, cancellationToken: ct);
-            },
+        }, cancellationToken: cancellationToken);
-            cancellationToken: cancellationToken);
 
         return await agent.DeserializeSessionAsync(sessionContent, cancellationToken: cancellationToken);
     }
 
     public override async ValueTask SaveSessionAsync(AIAgent agent, string conversationId, AgentSession session, CancellationToken cancellationToken = default)
     {
+        var key = GetKey(agent, conversationId);
         var sessionContent = await agent.SerializeSessionAsync(session, cancellationToken: cancellationToken);
-        await cache.SetAsync(GetCacheKey(conversationId), sessionContent, cancellationToken: cancellationToken);
+
+        await cache.SetAsync(key, sessionContent, cancellationToken: cancellationToken);
     }
 
-    private static string GetCacheKey(string conversationId) => $"agent-session:{conversationId}";
+    public override async ValueTask DeleteSessionAsync(AIAgent agent, string conversationId, CancellationToken cancellationToken = default)
+    {
+        var key = GetKey(agent, conversationId);
+        await cache.RemoveAsync(key, cancellationToken);
+    }
+
+    private static string GetKey(AIAgent agent, string conversationId)
+        => $"{agent.Id}:{conversationId}";
 }

SqlDatabaseVectorSearch/Services/VectorSearchService.cs

@@ -15,10 +15,8 @@ using SqlDatabaseVectorSearch.Workflows;
 namespace SqlDatabaseVectorSearch.Services;
 
 public partial class VectorSearchService([FromKeyedServices("EmbeddingWorkflow")] Workflow workflow, [FromKeyedServices("ReformulationAgent")] AIAgent reformulationAgent, [FromKeyedServices("RagAgent")] AIAgent ragAgent,
-    [FromKeyedServices("RagAgent")] AgentSessionStore sessionStore, IOptions<AppSettings> appSettingsOptions)
+    [FromKeyedServices("RagAgent")] AgentSessionStore sessionStore)
 {
-    private readonly AppSettings appSettings = appSettingsOptions.Value;
-
     public async Task<StoreEmbeddingResponse> ImportAsync(FormFileEmbeddingRequest request, CancellationToken cancellationToken = default)
     {
         await using var run = await InProcessExecution.RunAsync(workflow, request, cancellationToken: cancellationToken);
@@ -34,8 +32,9 @@ public partial class VectorSearchService([FromKeyedServices("EmbeddingWorkflow")
         return result;
     }
 
-    public async Task<RagResponse> AskQuestionAsync(Question question, bool reformulate = true, CancellationToken cancellationToken = default)
+    public async Task<Response> AskQuestionAsync(Question question, bool reformulate = true, CancellationToken cancellationToken = default)
     {
+        UsageDetails? reformulationUsage = null;
         var reformulatedQuestion = question.Text;
         var session = await sessionStore.GetSessionAsync(ragAgent, question.ConversationId.ToString(), cancellationToken);
 
@@ -44,62 +43,48 @@ public partial class VectorSearchService([FromKeyedServices("EmbeddingWorkflow")
             // Reformulates the question taking into account the context of the chat to perform keyword search and embeddings.
             var reformulationResponse = await reformulationAgent.RunAsync(question.Text, session, cancellationToken: cancellationToken);
             reformulatedQuestion = reformulationResponse.Text;
+            reformulationUsage = reformulationResponse.Usage;
         }
 
         var response = await ragAgent.RunAsync(reformulatedQuestion, session, cancellationToken: cancellationToken);
 
         await sessionStore.SaveSessionAsync(ragAgent, question.ConversationId.ToString(), session, cancellationToken);
 
-        session.TryGetInMemoryChatHistory(out var chatHistory);
+        return new(question.ConversationId, question.Text, reformulatedQuestion, response.Text, null, new TokenUsageResponse(reformulationUsage, response.Usage));
-
-        return new(question.ConversationId, question.Text, reformulatedQuestion, response.Text);
     }
 
     public async IAsyncEnumerable<Response> AskStreamingAsync(Question question, bool reformulate = true, [EnumeratorCancellation] CancellationToken cancellationToken = default)
     {
-        yield return null!;
+        UsageDetails? reformulationUsage = null;
+        var reformulatedQuestion = question.Text;
+        var session = await sessionStore.GetSessionAsync(ragAgent, question.ConversationId.ToString(), cancellationToken);
 
-        //// It the user doesn't want to reforulate the question, CreateContextAsync returns the original one.
+        if (reformulate)
-        //var (reformulatedQuestion, embeddingTokenCount, chunks) = await CreateContextAsync(question, reformulate, cancellationToken);
+        {
+            // Reformulates the question taking into account the context of the chat to perform keyword search and embeddings.
+            var reformulationResponse = await reformulationAgent.RunAsync(question.Text, session, cancellationToken: cancellationToken);
+            reformulatedQuestion = reformulationResponse.Text;
+            reformulationUsage = reformulationResponse.Usage;
+        }
 
-        //var answerStream = chatService.AskStreamingAsync(question.ConversationId, chunks, reformulatedQuestion.Text!, cancellationToken: cancellationToken);
+        // The first message contains the question and the corresponding token usage (if reformulated).
+        yield return new(question.ConversationId, question.Text, reformulatedQuestion, null, StreamState.Start, new(reformulationUsage, null));
 
-        //// The first message contains the question and the corresponding token usage (if reformulated).
+        var updates = new List<AgentResponseUpdate>();
-        //yield return new(question.Text, reformulatedQuestion.Text!, null, StreamState.Start, new(reformulatedQuestion.TokenUsage, embeddingTokenCount, null));
 
-        //TokenUsageResponse? tokenUsageResponse = null;
+        await foreach (var update in ragAgent.RunStreamingAsync(reformulatedQuestion, session, cancellationToken: cancellationToken))
-        //var fullAnswer = new StringBuilder();
+        {
-        //var citationsStarted = false;
+            updates.Add(update);
+            if (!string.IsNullOrEmpty(update.Text))
+            {
+                yield return new(question.ConversationId, update.Text, StreamState.Append);
+            }
+        }
 
-        //// Returns each token as a partial response.
+        await sessionStore.SaveSessionAsync(ragAgent, question.ConversationId.ToString(), session, cancellationToken);
-        //await foreach (var (token, tokenUsage) in answerStream)
+        var response = updates.ToAgentResponse();
-        //{
-        //    if (token is not null) // token can be null when the stream ends. 
-        //    {
-        //        fullAnswer.Append(token);
 
-        //        if (token.Contains('【'))
+        yield return new(question.ConversationId, null, null, response.Text, StreamState.End, new TokenUsageResponse(null, response.Usage));
-        //        {
-        //            // Citations start when we encounter a token containing a 【 character.
-        //            // We need to track it because we don't want to return the citations in the actual response.
-        //            citationsStarted = true;
-        //        }
-
-        //        if (!citationsStarted)
-        //        {
-        //            yield return new(token, StreamState.Append);
-        //        }
-        //    }
-        //    else
-        //    {
-        //        // Token usage is expected in the last message, when token is null.
-        //        tokenUsageResponse ??= tokenUsage is not null ? new(tokenUsage) : null;
-        //    }
-        //}
-
-        //// Extract citations at the end of streaming.
-        //var (_, citations) = ExtractCitations(fullAnswer.ToString());
-        //yield return new(null, StreamState.End, tokenUsageResponse, citations);
     }
 }
 

SqlDatabaseVectorSearch/SqlDatabaseVectorSearch.csproj

@@ -12,34 +12,34 @@
         <PackageReference Include="DocumentFormat.OpenXml" Version="3.5.1" />
         <PackageReference Include="EntityFrameworkCore.Exceptions.SqlServer" Version="10.0.1" />
         <PackageReference Include="FluentValidation.DependencyInjectionExtensions" Version="12.1.1" />
-        <PackageReference Include="Microsoft.Agents.AI.Hosting" Version="1.10.0-preview.260610.1" />
+        <PackageReference Include="Microsoft.Agents.AI.Hosting" Version="1.15.0-preview.260722.1" />
-        <PackageReference Include="Microsoft.Agents.AI.OpenAI" Version="1.10.0" />
+        <PackageReference Include="Microsoft.Agents.AI.OpenAI" Version="1.15.0" />
-        <PackageReference Include="Microsoft.Agents.AI.Workflows" Version="1.10.0" />
+        <PackageReference Include="Microsoft.Agents.AI.Workflows" Version="1.15.0" />
-        <PackageReference Include="Microsoft.Agents.AI.Workflows.Generators" Version="1.10.0">
+        <PackageReference Include="Microsoft.Agents.AI.Workflows.Generators" Version="1.15.0">
           <PrivateAssets>all</PrivateAssets>
           <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
         </PackageReference>
-        <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="10.0.9" />
+        <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="10.0.10" />
-        <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="10.0.9">
+        <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="10.0.10">
           <PrivateAssets>all</PrivateAssets>
           <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
         </PackageReference>
-        <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="10.0.9" />
+        <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="10.0.10" />
-        <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="10.0.9">
+        <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="10.0.10">
             <PrivateAssets>all</PrivateAssets>
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
         </PackageReference>
-        <PackageReference Include="Microsoft.Extensions.Caching.Hybrid" Version="10.7.0" />
+        <PackageReference Include="Microsoft.Extensions.Caching.Hybrid" Version="10.8.0" />
-        <PackageReference Include="Microsoft.Extensions.Http.Resilience" Version="10.7.0" />
+        <PackageReference Include="Microsoft.Extensions.Http.Resilience" Version="10.8.0" />
         <PackageReference Include="Microsoft.ML.Tokenizers" Version="2.0.0" />
         <PackageReference Include="Microsoft.ML.Tokenizers.Data.Cl100kBase" Version="2.0.0" />
         <PackageReference Include="Microsoft.ML.Tokenizers.Data.O200kBase" Version="2.0.0" />
         <PackageReference Include="MimeMapping" Version="4.0.0" />
         <PackageReference Include="MinimalHelpers.FluentValidation" Version="1.1.8" />
         <PackageReference Include="MinimalHelpers.Routing.Analyzers" Version="1.2.2" />
-        <PackageReference Include="PdfPig" Version="0.1.14" />
+        <PackageReference Include="PdfPig" Version="0.1.15" />
-        <PackageReference Include="Swashbuckle.AspNetCore.SwaggerUI" Version="10.2.1" />
+        <PackageReference Include="Swashbuckle.AspNetCore.SwaggerUI" Version="10.2.3" />
-        <PackageReference Include="TinyHelpers.AspNetCore" Version="4.2.12" />
+        <PackageReference Include="TinyHelpers.AspNetCore" Version="4.2.17" />
     </ItemGroup>
 
 </Project>