How to connect Obsidian to ChatGPT and Claude using MCP

Last update: 27/10/2026
Author Isaac
  • Integration of Obsidian with AI agents using the MCP Protocol for automated reading and writing of notes.
  • Implementation of Karpathy's three-layer architecture to delegate knowledge organization to the LLM.
  • Using RAG plugins such as Smart Connections and Copilot to chat with the local knowledge base.
  • Importance of context engineering and atomic notes to improve the accuracy of AI responses.

Conceptual representation of an interconnected digital brain, symbolizing the second brain in Obsidian.

Setting up a personal knowledge management system is often a rollercoaster ride. We start out full of enthusiasm, installing Obsidian, creating folders, and downloading plugins, but after a while, we realize that spending hours organizing notes is exhausting administrative work that steals time from what really matters: thinking and creating. This is where artificial intelligence comes in, not just as a chat program where we paste text, but as an engine that truly understands and manages our digital brain.

The real revolution comes when we stop treating AI as an external tool and integrate it through protocols like MCP (Model Context Protocol). This allows advanced agents like Claude not only to read our files but also to interact with our Obsidian vault in real time. It's no longer about endless copy-and-paste, but about having an assistant that knows our history, our ideas, and our projects, transforming a pile of Markdown files into a fully searchable strategic asset.

Why choose Obsidian to enhance your AI?

Modern and minimalist workspace with a laptop, representing the productivity of the knowledge worker.

Unlike other platforms that store everything in the cloud, Obsidian takes a local-first approach . This means your notes are simply text files on your own hard drive, giving you complete freedom. You're not locked into a single company's ecosystem; you can use any language model , either through cloud APIs or by running local models with tools like Ollama or LM Studio, ensuring absolute privacy.

When we compare this flexibility with options like Notion, the difference in terms of control is staggering. While other apps rely on the provider's AI, Obsidian lets you build a system where data flow is transparent and you have the ability to connect CLI agents that modify and organize your knowledge without anything leaving your machine, if you so choose. It's essentially the ideal foundation for a knowledge worker seeking data sovereignty.

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Essential plugins for chatting with your notes

If you don't want to get bogged down in terminal issues at first, there are community plugins that make the magic happen directly within the Obsidian interface. One of the most powerful is Smart Connections , which uses a technique called RAG (Recall Augmented Generation). Essentially, it indexes your notes into vectors so that when you ask a question, the AI ​​finds the most relevant snippets and answers you based solely on your information.

For those seeking versatility, Copilot is a fantastic option, allowing you to switch between different models (GPT, Claude, Gemini) and offering a QA mode for analyzing very long documents. On the other hand, if you need to improve your writing without leaving the document, Nova specializes in integrated editing, allowing you to expand or summarize text on the fly. And for the most security-conscious users, Smart Second Brain offers a fully local RAG pipeline, ensuring that not a single byte leaves your device.

The ultimate combo: Claude Code and the MCP Protocol

Digital spheres connected by bright lines, illustrating the MCP protocol as a bridge between AI and local data.

The next level of automation comes with the Model Context Protocol (MCP). This bridge allows Claude Code (Anthropic's command-line interface) to directly access your vault. It's no longer just about chatting with a note; the agent can now search the entire knowledge base , create new entries, and organize information according to your own rules.

To get this up and running, you need to install a dedicated MCP server for Obsidian using npm. Once configured in Claude's settings file, you can give it complex commands like "summarize the action points from my meetings this week" or ask it to design a project plan based on research notes scattered throughout your vault. It's literally as if the AI ​​has access to your memory and can draft documents that perfectly fit your current structure.

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The Karpathy Methodology: The LLM as an Architect

Abstract 3D data flow, representing the information organization and synthesis architecture of the Karpathy method.

Andrej Karpathy has proposed a radical paradigm shift: the second brain shouldn't be written by humans, but by AI. The common mistake is trying to manually categorize everything into complex folders, which often leads to the system being abandoned. The solution is a three-tier architecture where the user only provides the sources, and AI handles the grunt work of organization.

  • Sources Layer: This is the immutable zone where you store raw input (articles, transcripts, screenshots). This is where the original truth resides.
  • Wiki Layer: This is the dynamic zone. Only AI writes here, synthesizing information from sources into concepts, projects, and people pages.
  • Governance Layer (_CLAUDE.md): A master file that acts as the vault's constitution, telling the AI ​​how to name the files and where to store everything.

This workflow operates through three key actions: Ingest (when the AI ​​processes a source and updates the wiki), Query (when you consult your knowledge to obtain a summary), and Lint (a weekly audit where the AI ​​looks for contradictions or broken links in your notes). To feed this system, the Obsidian Web Clipper tool is essential, as it allows you to capture content from the web and send it directly to the sources layer with automatic summaries.

Context engineering tips to optimize your vault

For AI to avoid confusion and ensure accuracy, it's vital to implement contextual engineering . Simply dumping text isn't enough; it needs to be structured. Using descriptive filenames (including dates and topics) helps AI locate information faster. Similarly, incorporating metadata in YAML (tags, project status, participants) allows AI plugins to filter information with surgical precision.

Another key element is the creation of atomic notes . Instead of a massive 5000-word document, it's preferable to have concise concepts linked by wiki links . This makes the AI's retrieval process much more accurate, as it finds the exact piece of the puzzle instead of a confusing block of text. Ultimately, the quality of the AI's responses depends directly on how well-structured the knowledge is on your hard drive.

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Quick implementation guide in a few steps

Robotic hand interacting with a digital network, symbolizing AI's ability to query and manage the note vault.

If you want to get started today, the best approach is to download Obsidian and define a basic folder structure (Projects, Meetings, Research, and Ideas). Then, install Smart Connections and configure your Claude API or GPT to begin interacting with your notes. If you're more comfortable with the terminal, you can skip directly to installing the MCP server to connect Claude Code and automate your vault management.

For those who want to adopt the Karpathy method, simply create the files _CLAUDE.md, _index.md y _log.mdand give Claude a detailed prompt that allows him to scan your vault and propose a migration plan. Remember start with a small group of notes to adjust the prompts before processing thousands of files. The real value isn't in having the prettiest system, but in using AI daily to retrieve information and generate new ideas.

Having a system where artificial intelligence manages the flow of information transforms Obsidian from a simple notebook into an advanced productivity engine. By combining the privacy of local storage with the power of protocols like MCP and automated synthesis methodologies, we ensure that knowledge doesn't stagnate, but rather grows and refines itself, allowing us to focus on decision-making and creativity while AI takes care of the architecture of our digital memory.