Extract Context from Voice Notes with OpenRouter AI & Milvus for RAG Systems

Voice Note Context Extraction Pipeline with AI Agent & Vector Storage

This n8n template demonstrates how to automatically extract and store contextual information from voice notes using AI agents and vector databases for future retrieval.

How it works

  • Webhook trigger receives voice note data including title, transcript, and timestamp from external services (example here: voicenotes.com)
  • Field extraction isolates the key data fields (title, transcript, timestamp) for processing
  • AI Context Agent processes the transcript to extract meaningful context while:
    • Correcting speech-to-text errors
    • Converting first-person references to third-person facts
    • Filtering out casual conversation and focusing on significant information
  • Output formatting structures the extracted context with timestamps for embedding
  • File conversion prepares the context data for vector storage
  • Vector embedding uses OpenAI embeddings to create searchable representations
  • Milvus storage stores the embedded context for future retrieval in RAG applications

How to use

  • Configure the webhook endpoint to receive data from your voice note service
  • Set up credentials for OpenRouter (LLM), OpenAI (embeddings), and Milvus (vector storage)
  • Customize the AI agent's system prompt to match your context extraction needs
  • The workflow automatically processes incoming voice notes and stores extracted context

Requirements

  • OpenRouter account for LLM access
  • OpenAI API key for embeddings
  • Milvus vector database (cloud or self-hosted)
  • Voice note service with webhook capabilities (e.g., Voicenotes.com)

Customizing this workflow

  • Modify the context extraction prompt to focus on specific types of information (preferences, facts, relationships)
  • Add filtering logic to process only voice notes with specific tags or keywords
  • Integrate with other storage systems like Pinecone, Weaviate, or local vector databases
  • Connect to RAG systems to use the stored context for enhanced AI conversations
  • Add notification nodes to confirm successful context extraction and storage

Use cases

  • Personal AI assistant that remembers your preferences and context from voice notes
  • Knowledge management system for capturing insights from recorded thoughts
  • Content creation pipeline that extracts key themes from voice recordings
  • Research assistant that builds context from interview transcripts or meeting notes