KnowledgeBase/docs/design/feat-auto-title-generation.md

Feature Design: Automatic Title Generation (feat-auto-title-generation)

1. Overview

This feature automatically generates meaningful titles for uploaded documents and chat sessions using AI. It aims to replace generic filenames and "New Conversation" labels with content-aware titles, improving user experience and organization.

2. Requirements

2.1 Document Title Generation

• Trigger: Automatically triggered after text extraction (Fast or Precise mode).
• Process:
  1. Extract a sample of the document content (first 2,000 - 3,000 characters).
  2. Send the content to the default LLM with a specific generation prompt.
  3. Update the KnowledgeBase record with the generated title.
• Rules:
  • The title should be concise (less than 50 characters).
  • It should be in the user's preferred language (defaulting to the detected document language if possible).
  • Output should be "raw" (no preamble like "The title is...").

2.2 Chat Title Generation

• Trigger: Triggered after the first user message and its corresponding assistant response are recorded.
• Process:
  1. Collect the initial message pair.
  2. Send the pair to the default LLM with a generation prompt.
  3. Update the SearchHistory record's title field.
• Rules: Same as document titles.

3. Technical Design

3.1 Data Model Changes

• KnowledgeBase Entity: Add a title field (nullable, optional). If empty, fallback to originalName.
• SearchHistory Entity: No changes required (has title).

3.2 Backend Implementation

KnowledgeBaseService

• Add generateTitle(kbId: string) method.
• Hook into processFile after updateStatus(kbId, FileStatus.EXTRACTED).

ChatService / SearchHistoryService

• Add logic to check if the session title is still the default (usually the first message snippet) and trigger generateTitle(historyId: string) after the first assistant response.

Prompt Design

• Document Prompt:

  You are a document analyzer. Read the provided text and generate a concise, professional title (max 50 chars). 
  Return ONLY the title.
  Language: {userLanguage}
  Text: {contentSample}
  

• Chat Prompt:

  Based on the following conversation snippet, generate a short, descriptive title (max 50 chars) that summarizes the topic.
  Return ONLY the title.
  Language: {userLanguage}
  Snippet:
  User: {userMessage}
  AI: {aiResponse}
  

4. Verification Plan

Automated Tests

• Integration tests in KnowledgeBaseService to verify the title field is updated after processing.
• Mock LLM responses to ensure the title update logic works.

Manual Verification

• Upload various files (PDF, Word, TXT) and verify the displayed title in the knowledge base list.
• Start a new chat, send a message, and check the sidebar for the updated session title.