Basic Memory
Reference

Technical Information

Technical details about Basic Memory implementation, architecture, licensing, and Model Context Protocol integration
This page describes the architecture of the open-source Basic Memory project. Basic Memory Cloud builds on this foundation with hosted infrastructure and additional features.

Architecture

Basic Memory consists of:

  • Core Knowledge Engine — Parses and indexes Markdown files
  • Database — Provides fast querying and search
  • MCP Server — Implements the Model Context Protocol
  • CLI Tools — Command-line utilities for management
  • File Watcher — Monitors file changes and indexes the database
The system follows a file-first architecture where all knowledge is represented in standard Markdown files and the database serves as a secondary index.

Model Context Protocol (MCP)

Basic Memory implements the Model Context Protocol, an open standard for enabling AI models to access external tools:

  • Standardized Interface — Common protocol for tool integration
  • Tool Registration — Basic Memory registers as a tool provider
  • Asynchronous Communication — Enables efficient interaction with AI models
  • Standardized Schema — Structured data exchange format

Integration with Claude Desktop uses the MCP to grant Claude access to your knowledge base through a set of specialized tools that search, read, and write knowledge.

Licensing

Basic Memory is licensed under the GNU Affero General Public License v3.0 (AGPL-3.0):

  • Free Software — You can use, study, share, and modify the software
  • Copyleft — Derivative works must be distributed under the same license
  • Network Use — Network users must be able to receive the source code
  • Commercial Use — Allowed, subject to license requirements
The AGPL license ensures Basic Memory remains open source while protecting against proprietary forks.

Source Code

Basic Memory is developed as an open-source project:

  • GitHub Repositoryhttps://github.com/basicmachines-co/basic-memory
  • Issue Tracker — Report bugs and request features on GitHub
  • Contributions — Pull requests are welcome following the contributing guidelines
  • Documentation — Source for this documentation is also available in the repository

Data Storage and Privacy

Basic Memory is designed with privacy as a core principle:

Privacy-First Design:
  • Local-First: All data remains on your machine
  • No Cloud Dependency: No remote servers or accounts required
  • Telemetry: Optional and disabled by default
  • Standard Formats: All data is stored in standard file formats you control

Implementation Details

Knowledge in Basic Memory is organized as a semantic graph:

Entities

Distinct concepts represented by Markdown documents

Observations

Categorized facts and information about entities

Relations

Connections between entities that form the knowledge graph

This structure emerges from simple text patterns in standard Markdown:

Example Markdown Input

---
title: Coffee Brewing Methods
type: note
permalink: coffee/coffee-brewing-methods
tags:
- '#coffee'
- '#brewing'
- '#methods'
- '#demo'
---

# Coffee Brewing Methods

An exploration of different coffee brewing techniques, their characteristics, and how they affect flavor extraction.

## Overview

Coffee brewing is both an art and a science. Different brewing methods extract different compounds from coffee beans,
resulting in unique flavor profiles, body, and mouthfeel. The key variables in any brewing method are:

- Grind size
- Water temperature
- Brew time
- Coffee-to-water ratio
- Agitation/turbulence

## Observations

- [principle] Coffee extraction follows a predictable pattern: acids extract first, then sugars, then bitter compounds
#extraction
- [method] Pour over methods generally produce cleaner, brighter cups with more distinct flavor notes #clarity

## Relations

- requires [[Proper Grinding Technique]]
- affects [[Flavor Extraction]]

Parsed JSON Structure

Resulting JSON Entity Structure

{
  "entities": [
    {
      "permalink": "coffee/coffee-brewing-methods",
      "title": "Coffee Brewing Methods",
      "file_path": "Coffee Notes/Coffee Brewing Methods.md",
      "entity_type": "note",
      "entity_metadata": {
        "title": "Coffee Brewing Methods",
        "type": "note",
        "permalink": "coffee/coffee-brewing-methods",
        "tags": "['#coffee', '#brewing', '#methods', '#demo']"
      },
      "checksum": "bfa32a0f23fa124b53f0694c344d2788b0ce50bd090b55b6d738401d2a349e4c",
      "content_type": "text/markdown",
      "observations": [
        {
          "category": "principle",
          "content": "Coffee extraction follows a predictable pattern: acids extract first, then sugars, then bitter compounds #extraction",
          "tags": [
            "extraction"
          ],
          "permalink": "coffee/coffee-brewing-methods/observations/principle/coffee-extraction-follows-a-predictable-pattern-acids-extract-first-then-sugars-then-bitter-compounds-extraction"
        },
        {
          "category": "method",
          "content": "Pour over methods generally produce cleaner, brighter cups with more distinct flavor notes #clarity",
          "tags": [
            "clarity"
          ],
          "permalink": "coffee/coffee-brewing-methods/observations/method/pour-over-methods-generally-produce-cleaner-brighter-cups-with-more-distinct-flavor-notes-clarity"
        }
      ],
      "relations": [
        {
          "from_id": "coffee/coffee-bean-origins",
          "to_id": "coffee/coffee-brewing-methods",
          "relation_type": "pairs_with",
          "permalink": "coffee/coffee-bean-origins/pairs-with/coffee/coffee-brewing-methods",
          "to_name": "Coffee Brewing Methods"
        },
        {
          "from_id": "coffee/flavor-extraction",
          "to_id": "coffee/coffee-brewing-methods",
          "relation_type": "affected_by",
          "permalink": "coffee/flavor-extraction/affected-by/coffee/coffee-brewing-methods",
          "to_name": "Coffee Brewing Methods"
        }
      ],
      "created_at": "2025-03-06T14:01:23.445071",
      "updated_at": "2025-03-06T13:34:48.563606"
    }
  ]
}

Basic Memory understands how to build context via its semantic graph.

Entity Model

Basic Memory's core data model consists of:

  • Entities — Documents in your knowledge base
  • Observations — Facts or statements about entities
  • Relations — Connections between entities
  • Tags — Additional categorization for entities and observations

The system parses Markdown files to extract this structured information while preserving the human-readable format.

Files as Source of Truth

Plain Markdown files store all knowledge, making it accessible with any text editor and easy to version with git.

mermaid
Rendering diagram...

Database

The database maintains the knowledge graph topology for fast queries and semantic traversal. It contains:

  • Knowledge Graph Schema — Database tables for the knowledge graph structure
  • Search Index — Full text search index across the knowledge base

Sync Process

The sync process:

Detect Changes

Detects changes to files in the knowledge directory

Parse Files

Parses modified files to extract structured data

Update Database

Updates the database with changes

Resolve References

Resolves forward references when new entities are created

Update Search Index

Updates the search index for fast querying

Search Engine

The search functionality:

  • Hybrid Search — Uses a combination of full-text search and semantic matching
  • Comprehensive Indexing — Indexes observations, relations, and content
  • Pattern Matching — Supports wildcards and pattern matching in memory:// URLs
  • Graph Traversal — Traverses the knowledge graph to follow relationships
Results are ranked by relevance to the query using advanced scoring algorithms.

System Architecture

Component Interaction

The Basic Memory system is built with a modular architecture:

Markdown Files — The foundation of your knowledge base

  • Human-Readable — Edit with any text editor
  • Version Control Friendly — Works seamlessly with Git
  • Standard Format — Plain Markdown with YAML frontmatter
  • Complete Ownership — Your files, your control

Performance Characteristics

  • Local Performance — All operations are local with no network latency
  • Scalability — Handles knowledge bases with thousands of documents
  • Resource Efficiency — Minimal CPU and memory footprint

Development Philosophy

Basic Memory embodies several key principles:

Core Principles:
  • Local-First: Your data stays on your machine
  • Open Standards: Uses standard formats and protocols
  • Human-Readable: Everything is accessible without special tools
  • AI-Native: Designed specifically for AI collaboration
  • Privacy-Preserving: No data collection or tracking