Create custom reasoning patterns for AI agents with GraphRAG & knowledge ontology
Teach your AI agent HOW to think, not WHAT to think
This workflow demonstrates how you can build an AI agent in n8n that uses the reasoning logic you define. So an LLM learns a way of thinking, which you can then apply to multiple problems:
- Make an AI chatbot that knows how to convince anybody using the "Getting to Yes" method
- Build an LLM workflow that uses Ray Dalio's principles to spot investment opportunities
- Create an AI agent crew of interdisciplinary thinkers: e.g. a specialist in psychology who gives an advice on education programmes.

How it works
This template uses the n8n AI agent node as an orchestrating agent that has access to a certain reasoning logic defined by an InfraNodus knowledge graph.
This graph contains a list of reasoning rules (ontology), which is extracted to provide an advice that is relevant to the original prompt. It uses GraphRAG under the hood to traverse the parts of the graph relevant to the query.
This advice and the reasoning logic extracted is then used by the AI agent to generate a response that is relevant to the user's query but that uses the reasoning logic provided through the graph.
Here's a description step by step:
- The user submits a question using the AI chatbot (n8n interface, in this case, a web form that can be embedded to any website, or a webhook that can be connected to a Telegram / WhatsApp bot)
- The AI agent node accesses the Reasoning Logic HTTP InfraNodus nodes. The description of AI agent and the description of the reasoning InfraNodus node provides the agent with an understanding of how to rephrase the original question to retrieve relevant reasoning logic.
- The request is sent to the InfraNodus node. It provides a response that contains the reasoning logic needed to answer the question.
- This reasoning logic is then sent back to an LLM along with the original query to produce the response.
InfraNodus uses GraphRAG under the hood:
- convert user query into graph
- find the overlap with the reasoning graph (using n=1 or more hops to include more relations)
- use similarity search to get additional parts of the graph
- generate a response based on this intersection as well as the context provided
- provide information about the underlying structure
How to use
You need an InfraNodus account to use this workflow.
- Create an InfraNodus account
- Get the API key at https://infranodus.com/api-access and create a Bearer authorization key for the InfraNodus HTTP nodes.
- Create a separate knowledge graph for the reasoning logic
- Use the AI ontology creator to generate an ontology for a certain topic or text using AI. Then augment it with your own data. See our help article on creating ontologies for detailed instructions
- For each graph, go to the workflow, paste the name of the graph into the request JSON
bodynamefield. - Change the system prompt in the AI agent node to reflect the nature of your reasoning logic. For instance, if it's an expert in interactions, you specify that, if it's a psychology expert, you need to specify that as well.
- Change the description of the reasoning node (HTTP tool). Use the InfraNodus
summaryandProject Notes>RAG promptbuttons to generate a description for the reasoning logic, which you can then reuse in your workflow. - add the LLM key to the OpenAI node (or to the model of your choice) and launch the workflow
Requirements
- An InfraNodus account and API key
- An OpenAI (or any other LLM) API key
Customizing this workflow
You can use this same workflow with a Telegram bot, so you can interact with it using Telegram. There are many more customizations available.
Check out the complete guide at https://support.noduslabs.com/hc/en-us/articles/21429518472988-Using-Knowledge-Graphs-as-Reasoning-Experts
Also check out the video tutorial with a demo:
Create Custom Reasoning Patterns for AI Agents with GraphRAG & Knowledge Ontology
This n8n workflow demonstrates how to build a basic AI agent that can engage in conversational interactions, leveraging a large language model (LLM) and a simple memory mechanism. It serves as a foundational example for creating custom reasoning patterns, which can be extended for more complex GraphRAG and knowledge ontology applications.
What it does
This workflow automates the following steps:
- Listens for Chat Messages: It acts as a conversational agent, waiting for incoming chat messages.
- Initializes an AI Agent: Upon receiving a message, it activates a LangChain AI Agent.
- Configures the Language Model: The agent uses an OpenAI Chat Model for processing natural language and generating responses.
- Maintains Conversation History: A simple memory buffer is employed to retain context from previous interactions, allowing for more coherent conversations.
- Processes and Responds: The AI agent processes the incoming message, consults its memory, and generates a relevant response using the configured OpenAI model.
Prerequisites/Requirements
To use this workflow, you will need:
- n8n Instance: A running n8n instance (cloud or self-hosted).
- OpenAI API Key: An API key for accessing the OpenAI Chat Model. This needs to be configured as an n8n credential.
- LangChain Nodes: Ensure the
@n8n/n8n-nodes-langchainpackage is installed and enabled in your n8n instance.
Setup/Usage
- Import the Workflow: Download the provided JSON and import it into your n8n instance.
- Configure Credentials:
- Locate the "OpenAI Chat Model" node.
- Click on the "Credential" field and select or create a new "OpenAI API" credential.
- Enter your OpenAI API Key into the credential setup.
- Activate the Workflow: Toggle the workflow to "Active" in the top right corner of the n8n editor.
- Start Chatting: The "When chat message received" trigger will now be active. You can interact with this agent through a chat interface connected to n8n (e.g., n8n's built-in chat UI if available, or by connecting it to a chat platform via another trigger node, which is not included in this basic example).
This workflow provides a basic conversational agent. To extend it for GraphRAG and knowledge ontology, you would typically add:
- Vector Store Nodes: To store and retrieve knowledge graphs or document embeddings.
- Tool Nodes: To allow the AI agent to interact with external systems, databases, or APIs.
- More Complex Memory: For longer-term memory and more sophisticated context management.
- Data Processing Nodes: To extract, transform, and load data into your knowledge ontology.
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