Knowledge Graph Memory MCP server for AI agents

The Knowledge Graph Memory Server is an MCP (Model Context Protocol) implementation that provides persistent memory capabilities using a local knowledge graph. This allows AI assistants like Claude to remember information about users across chat sessions by storing and retrieving structured data.

Installation Options

Docker Setup for Claude Desktop

To use the memory server with Claude Desktop via Docker:

Add the following configuration to your claude_desktop_config.json file:

{
  "mcpServers": {
    "memory": {
      "command": "docker",
      "args": ["run", "-i", "-v", "claude-memory:/app/dist", "--rm", "mcp/memory"]
    }
  }
}

NPX Setup for Claude Desktop

To use the memory server with Claude Desktop via NPX:

Add the following configuration to your claude_desktop_config.json file:

{
  "mcpServers": {
    "memory": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-memory"
      ]
    }
  }
}

Custom Configuration

You can customize the server using environment variables:

{
  "mcpServers": {
    "memory": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-memory"
      ],
      "env": {
        "MEMORY_FILE_PATH": "/path/to/custom/memory.json"
      }
    }
  }
}

Available environment variables:

MEMORY_FILE_PATH: Path to the memory storage JSON file (default: memory.json in the server directory)

VS Code Installation

Manual Installation

Add one of the following JSON blocks to your VS Code User Settings file (access via Ctrl + Shift + P and type Preferences: Open Settings (JSON)):

For NPX:

{
  "mcp": {
    "servers": {
      "memory": {
        "command": "npx",
        "args": [
          "-y",
          "@modelcontextprotocol/server-memory"
        ]
      }
    }
  }
}

For Docker:

{
  "mcp": {
    "servers": {
      "memory": {
        "command": "docker",
        "args": [
          "run",
          "-i",
          "-v",
          "claude-memory:/app/dist",
          "--rm",
          "mcp/memory"
        ]
      }
    }
  }
}

Alternatively, you can add this configuration to .vscode/mcp.json in your workspace (without the mcp key).

Using the Memory Server

Core Concepts

Entities

Entities are the main nodes in the knowledge graph, with properties:

Unique name (identifier)
Entity type (e.g., "person", "organization")
List of observations

Example entity:

{
  "name": "John_Smith",
  "entityType": "person",
  "observations": ["Speaks fluent Spanish"]
}

Relations

Relations connect entities in the knowledge graph:

{
  "from": "John_Smith",
  "to": "Anthropic",
  "relationType": "works_at"
}

Observations

Observations are discrete facts about entities:

{
  "entityName": "John_Smith",
  "observations": [
    "Speaks fluent Spanish",
    "Graduated in 2019",
    "Prefers morning meetings"
  ]
}

API Tools

The memory server provides several tools:

create_entities: Add new entities to the knowledge graph
create_relations: Create connections between entities
add_observations: Add new facts to existing entities
delete_entities: Remove entities and their relations
delete_observations: Remove specific observations
delete_relations: Remove specific relations
read_graph: Retrieve the entire knowledge graph
search_nodes: Search for entities matching a query
open_nodes: Retrieve specific entities by name

System Prompt Example

Here's an example system prompt for Claude to use with the memory server:

Follow these steps for each interaction:

1. User Identification:
   - You should assume that you are interacting with default_user
   - If you have not identified default_user, proactively try to do so.

2. Memory Retrieval:
   - Always begin your chat by saying only "Remembering..." and retrieve all relevant information from your knowledge graph
   - Always refer to your knowledge graph as your "memory"

3. Memory
   - While conversing with the user, be attentive to any new information that falls into these categories:
     a) Basic Identity (age, gender, location, job title, education level, etc.)
     b) Behaviors (interests, habits, etc.)
     c) Preferences (communication style, preferred language, etc.)
     d) Goals (goals, targets, aspirations, etc.)
     e) Relationships (personal and professional relationships up to 3 degrees of separation)

4. Memory Update:
   - If any new information was gathered during the interaction, update your memory as follows:
     a) Create entities for recurring organizations, people, and significant events
     b) Connect them to the current entities using relations
     c) Store facts about them as observations

You can use this prompt in the "Custom Instructions" field of a Claude.ai Project.

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "memory" '{"command":"npx","args":["-y","@modelcontextprotocol/server-memory"]}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "memory": {
            "command": "npx",
            "args": [
                "-y",
                "@modelcontextprotocol/server-memory"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
Windows: %APPDATA%\Claude\claude_desktop_config.json
Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "memory": {
            "command": "npx",
            "args": [
                "-y",
                "@modelcontextprotocol/server-memory"
            ]
        }
    }
}

3. Restart Claude Desktop for the changes to take effect