Let data sources be searched page by page with a query of their own

app/MindWork AI Studio/Settings/IDataSource.cs

@@ -22,10 +22,10 @@ public interface IDataSource : IConfigurationObject
     public DataSourceType Type { get; init; }
 
     /// <summary>
-    /// The maximum number of matches to return when retrieving data from the ERI server.
+    /// The maximum number of matches one retrieval returns. Searched page by page, it is the size of a page.
     /// </summary>
     public ushort MaxMatches { get; init; }
-    
+
     /// <summary>
     /// Perform the data retrieval process.
     /// </summary>
@@ -34,4 +34,21 @@ public interface IDataSource : IConfigurationObject
     /// <param name="token">The cancellation token.</param>
     /// <returns>The retrieved data context.</returns>
     public Task<IReadOnlyList<IRetrievalContext>> RetrieveDataAsync(IContent lastUserPrompt, ChatThread thread, CancellationToken token = default);
+
+    /// <summary>
+    /// Search the data source for a query of its own, one page at a time.
+    /// </summary>
+    /// <remarks>
+    /// Unlike the retrieval above, the query need not be what the user wrote last: Semantic Search
+    /// lets the model work it out from the conversation, and search as often as it takes. The first
+    /// page holds what the retrieval above finds for the same text. How the pages are cut is
+    /// described in RetrievalPaging.
+    /// </remarks>
+    /// <param name="query">What to search for.</param>
+    /// <param name="page">The page to retrieve, from 1 up to RetrievalPaging.GetLastPage for MaxMatches.</param>
+    /// <param name="thread">The chat thread.</param>
+    /// <param name="token">The cancellation token.</param>
+    /// <returns>The retrieved data contexts of this page, and whether the next page is worth asking for.</returns>
+    /// <exception cref="ArgumentOutOfRangeException">The page is below 1 or beyond the last page.</exception>
+    public Task<RetrievalPage> RetrieveDataAsync(string query, int page, ChatThread thread, CancellationToken token = default);
 }