Fix document availability instructions template

src/Primitives/CrestApps.Core.AI.Documents/Tools/ReadTabularDataTool.cs

@@ -1,13 +1,16 @@
 using System.Text.Json;
+using CrestApps.Core.AI.Documents.Models;
 using CrestApps.Core.AI.Extensions;
 using CrestApps.Core.AI.Models;
 using CrestApps.Core.AI.Orchestration;
 using CrestApps.Core.AI.Tooling;
 using Cysharp.Text;
 
 using Microsoft.Extensions.AI;
+using Microsoft.Extensions.DataIngestion;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
 
 namespace CrestApps.Core.AI.Documents.Tools;
 
@@ -155,6 +158,9 @@ sessionObj is AIChatSession session &&
             return $"Document '{document.FileName}' is not a recognized tabular format. Use 'read_document' instead.";
         }
 
+        var extension = Path.GetExtension(document.FileName);
+        var options = arguments.Services.GetRequiredService<IOptions<ChatDocumentsOptions>>().Value;
+
         // Reconstruct full text from chunks.
         var chunkStore = arguments.Services.GetService<IAIDocumentChunkStore>();
 
@@ -169,6 +175,69 @@ sessionObj is AIChatSession session &&
 
         if (chunks.Count == 0)
         {
+            if (!options.EmbeddableFileExtensions.Contains(extension))
+            {
+                var fileStore = arguments.Services.GetService<IDocumentFileStore>();
+
+                if (fileStore is null || string.IsNullOrWhiteSpace(document.StoredFilePath))
+                {
+                    logger.LogWarning("AI tool '{ToolName}' failed: file store is not available or file path is missing for non-embeddable tabular document '{FileName}'.", Name, document.FileName);
+
+                    return $"Document '{document.FileName}' has no extractable text content.";
+                }
+
+                var reader = arguments.Services.GetKeyedService<IngestionDocumentReader>(extension);
+
+                if (reader is null)
+                {
+                    logger.LogWarning("AI tool '{ToolName}' failed: no document reader registered for non-embeddable tabular document '{FileName}'.", Name, document.FileName);
+
+                    return $"Document '{document.FileName}' has no extractable text content.";
+                }
+
+                await using var stream = await fileStore.GetFileAsync(document.StoredFilePath);
+
+                if (stream is null)
+                {
+                    logger.LogWarning("AI tool '{ToolName}' failed: tabular document file not found at path '{Path}'.", Name, document.StoredFilePath);
+
+                    return $"Document '{document.FileName}' has no extractable text content.";
+                }
+
+                try
+                {
+                    var mediaType = MediaTypeHelper.InferMediaType(extension, document.ContentType);
+
+                    var ingestionDoc = await reader.ReadAsync(stream, document.FileName, mediaType, cancellationToken);
+
+                    var tabularText = string.Join(Environment.NewLine, ingestionDoc.EnumerateContent()
+                        .Select(element => element.Text)
+                        .Where(content => !string.IsNullOrWhiteSpace(content)));
+
+                    if (string.IsNullOrWhiteSpace(tabularText))
+                    {
+                        logger.LogWarning("AI tool '{ToolName}' failed: extracted text is empty for non-embeddable tabular document '{FileName}'.", Name, document.FileName);
+
+                        return $"Document '{document.FileName}' has no extractable text content.";
+                    }
+
+                    var tabularContent = LimitTabularRows(tabularText, maxRows);
+
+                    if (logger.IsEnabled(LogLevel.Debug))
+                    {
+                        logger.LogDebug("AI tool '{ToolName}' completed.", Name);
+                    }
+
+                    return $"[Tabular data from: {document.FileName}]\n\n{tabularContent}";
+                }
+                catch (Exception ex)
+                {
+                    logger.LogWarning(ex, "AI tool '{ToolName}' failed: unable to read non-embeddable tabular document '{FileName}' from stored file.", Name, document.FileName);
+
+                    return $"Document '{document.FileName}' has no extractable text content.";
+                }
+            }
+
             logger.LogWarning("AI tool '{ToolName}' failed: no chunks found for document '{FileName}'.", Name, document.FileName);
 
             return $"Document '{document.FileName}' has no extractable text content.";

src/Primitives/CrestApps.Core.AI/Templates/Prompts/document-availability.md

@@ -57,6 +57,7 @@ Answer only from the uploaded documents.
 If the uploaded documents do not contain the answer, say so instead of using general knowledge.
 {% endif %}
 {% endif %}
+{% endif %}
 
 {% if hasUserSuppliedDocuments %}
 ### Available documents: