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CASE STUDY 04 / 08 · KNOWLEDGE SYSTEMS

RAG Knowledge Agent

The AI Customer Agent Example prepares incoming Gmail messages, classifies them as sales rep or sales FAQ, and uses an OpenAI agent with access to a Supabase vector store to support its response. The workflow can draft an email using a Gmail tool and sends a Telegram message.

THE WORKFLOWn8n · OpenAI (chat and embeddings) · Supabase vector store · Gmail · Telegram
WORKFLOW / 04KNOWLEDGE SYSTEMS
Screenshot: AI Customer Agent Example workflow in n8n

01 / THE PROBLEM

The challenge.

AI assistants often need access to specific business information instead of relying only on general AI knowledge.

02 / THE SOLUTION

The connected answer.

The AI Customer Agent Example prepares incoming Gmail messages, classifies them as sales rep or sales FAQ, and uses an OpenAI agent with access to a Supabase vector store to support its response. The workflow can draft an email using a Gmail tool and sends a Telegram message.

RAG means the assistant looks through trusted information before it answers, instead of relying only on general AI knowledge.

03 / HOW IT WORKS

Inside the logic.

A new email triggers the workflow through Gmail.

The email body is prepared, then a text classifier decides what kind of email it is — for example a message from a sales rep or a sales FAQ question — and routes it accordingly.

An AI agent takes over. It has access to a Supabase vector store that holds the business’s knowledge, and it uses OpenAI embeddings to find the most relevant information before answering. The agent can also draft an email through a Gmail tool.

A Telegram message is sent with the outcome, so someone can see what the agent did.

  1. 01

    Gmail trigger

    Receive the incoming email.

  2. 02

    Prepare email body

    Format the message for classification.

  3. 03

    Text classifier

    Route to sales rep or sales FAQ.

  4. 04

    AI agent

    OpenAI chat model can search a Supabase vector store with OpenAI embeddings and draft an email through a Gmail tool.

  5. 05

    Telegram message

    Send a message through Telegram.

BUILD GUIDE

How to build it.

A practical guide to recreating this workflow in n8n.

  1. 01

    Prepare the knowledge base

    Create a Supabase project and enable its vector store table. Load your business documents into it using a separate n8n workflow with OpenAI Embeddings and a Supabase Vector Store insert node.

  2. 02

    Add the Gmail trigger

    Connect Gmail and add a Gmail Trigger that watches for new emails in the inbox.

  3. 03

    Clean the email body

    Use a Set (Edit Fields) node to keep the sender, subject and plain-text body.

  4. 04

    Classify the email

    Add a Text Classifier node with categories such as "sales rep" and "sales FAQ", each with a short description, so emails go down the right path.

  5. 05

    Build the RAG agent

    Add an AI Agent node with an OpenAI Chat Model. Attach a Supabase Vector Store tool (using OpenAI Embeddings) so it searches your documents before answering, plus a Gmail tool so it can create a draft reply.

  6. 06

    Send a Telegram notification

    Create a Telegram bot, add its credentials, and send a message summarising what the agent did.

  7. 07

    Test and activate

    Send test emails of each type, check the retrieved context and draft, refine the prompt, then activate.

04 / TECHNOLOGY USED

Connected tools.

n8nOpenAI (chat and embeddings)Supabase vector storeGmailTelegram

05 / WORKFLOW SCREENSHOTS

Behind the build.

Screenshot: AI Customer Agent Example workflow in n8n

Select the image to enlarge.

06 / RESULT

What it demonstrates.

An agent that answers from the business’s own knowledge instead of guessing, and routes different kinds of emails differently.

WHAT THIS PROJECT SHOWS

RAG (retrieval-augmented generation)Text classificationTool-using AI agents

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