Persistent memory for MCP clients.

mcp-prose-memory gives an agent a small, durable place to keep facts across sessions. It stores memory as JSON, keeps facts grouped by section, and exposes one tool for careful add, remove, replace, and view operations.

It is built for memory that should survive restarts without becoming a loose text file that slowly drifts out of shape.

Docs · Changelog · Contributing · Security

• JSON memory storage with a stable schema
• Compact structured facts with optional key, value, source, and confidence
• Atomic writes through temp-file replacement
• Atomic fact operations: add, remove, replace, view
• Sectioned context organization for general clients and local assistant memory
• Case-insensitive duplicate detection
• Strict line-number validation for remove and replace
• Automatic normalization for older or partial JSON documents
• Compact memory_context output with section and character-budget filters
• Limits: 30 facts per section, 300 characters per fact, 80 characters per structured key
• Configurable storage path via environment variable

Full setup guide: Docs.

Runtime: Node >= 18.

npm install -g mcp-prose-memory

Or run with npx:

npx mcp-prose-memory

Configuration reference: Docs.

Default storage is ~/.mcp-prose-memory/memory.json. Override it with MEMORY_PATH.

If you used an older release with a client-specific default memory location, either move that JSON file to the new default path or set MEMORY_PATH to the existing file.

Add a server entry like this to your MCP client config:

{
  "mcpServers": {
    "memory": {
      "command": "npx",
      "args": ["mcp-prose-memory"]
    }
  }
}

Add a server entry like this to your CLI MCP config:

{
  "mcpServers": {
    "memory": {
      "command": "npx",
      "args": ["mcp-prose-memory"]
    }
  }
}

{
  "mcpServers": {
    "memory": {
      "command": "npx",
      "args": ["mcp-prose-memory"],
      "env": {
        "MEMORY_PATH": "/path/to/your/memory.json"
      }
    }
  }
}

The memory file is JSON with arrays of facts per section:

{
  "version": 5,
  "updated": "2025-01-15T10:30:00.000Z",
  "sections": {
    "work": ["Fact 1", "Fact 2"],
    "personal": ["Lives in Berlin", "Prefers dark mode"],
    "top_of_mind": [],
    "history": ["Completed project X"],
    "instructions": ["Be concise"],
    "user_preferences": [
      {
        "key": "answer_style",
        "value": "Prefers concise answers",
        "confidence": "high",
        "source": "user_explicit",
        "createdAt": "2025-01-15T10:30:00.000Z",
        "updatedAt": "2025-01-15T10:30:00.000Z"
      }
    ]
  }
}

If the file does not exist, the server starts with an empty document. If the file is invalid JSON, the server fails the operation instead of wiping memory.

Tools reference: Docs.

Single tool for all memory operations. The command parameter selects the action.

Commands:

Show all memories or filter by section.

{"command": "view"}
{"command": "view", "section": "work"}

Add a fact to a section.

{"command": "add", "section": "personal", "fact": "Lives in Berlin"}

Structured compact facts are also supported:

{"command": "add", "section": "user_preferences", "key": "answer_style", "value": "Prefers concise answers"}

Add a structured fact or replace the existing fact with the same key.

{"command": "upsert", "section": "user_preferences", "key": "answer_style", "value": "Prefers concise and direct answers"}

Remove a fact by line number.

{"command": "remove", "section": "work", "line": 3}

Update a fact by line number.

{"command": "replace", "section": "top_of_mind", "line": 1, "fact": "Working on new project"}

Returns memory for session initialization. Clients can request compact bounded context.

{}

{"format": "compact", "sections": ["user_profile", "user_preferences"], "maxChars": 1500}

git clone https://github.com/gabrimatic/mcp-prose-memory.git
cd mcp-prose-memory
npm ci
npm test
npm run check

npm test builds the TypeScript source and runs store-level plus real MCP stdio smoke tests. npm run check also runs a production dependency audit and verifies the npm package contents with npm pack --dry-run.

prepublishOnly runs the same check before publishing.

• Changes: CHANGELOG.md
• Contributions: CONTRIBUTING.md
• Security reports: SECURITY.md
• Issues: GitHub Issues

By Soroush

MIT