Introduction to r3

r3 is an open-source local Redis memory MCP server that gives AI assistants persistent memory. Install with npx @n3wth/r3 to add context that survives across sessions.

What is r3?

r3 is an open-source MCP server designed specifically for AI applications, particularly Large Language Models (LLMs) and agents. It provides a local memory layer that combines:

  • Embedded Redis for lightning-fast memory retrieval (sub-millisecond response times)
  • Local vector search for semantic memory queries
  • Knowledge graphs for automatic entity extraction and relationship mapping
  • Optional cloud sync via Mem0 for persistence across machines

Key Features

Open Source and Local-First

r3 runs entirely on your machine with zero external dependencies. No API keys required to get started.

Embedded Redis

Automatically starts an embedded Redis server for fast local caching. No separate Redis installation needed.

Simple Integration

Works with Antigravity CLI. One command to install: npx @n3wth/r3.

AI Intelligence Built-In

Real vector embeddings, entity extraction, and knowledge graphs all running locally.

Why r3?

The Problem

Traditional AI memory systems force you to choose between:

  • Speed: Local storage is fast but volatile and doesn't scale
  • Persistence: Cloud storage is reliable but adds latency
  • Privacy: Cloud solutions require sending your data to third parties

The Solution

r3 provides an open-source, local-first memory layer that:

  • Serves memories from embedded Redis in under 5ms
  • Runs 100% locally with no external API calls required
  • Optionally syncs to cloud for cross-machine persistence
  • Handles failures gracefully with automatic fallback

Core Concepts

Memory

A memory is a piece of information stored with metadata including:

  • Content (text, structured data, embeddings)
  • User association
  • Priority level (low, medium, high, critical)
  • Timestamps and access patterns
  • Custom metadata

Cache Layers

Recall uses a multi-tier caching strategy:

  • Hot Cache: Most frequently accessed memories (Redis)
  • Warm Storage: Recent or important memories (Mem0)
  • Cold Storage: All historical memories (Cloud)

Synchronization

Automatic bi-directional sync ensures:

  • New memories are cached and persisted
  • Cache misses are filled from cloud
  • Updates propagate to all layers
  • Consistency is maintained

Use Cases

AI Assistants

Give your AI assistants long-term memory about user preferences, conversation history, and learned behaviors.

Customer Support Bots

Remember customer issues, preferences, and resolution history across all interactions.

Personalization Engines

Build recommendation systems that remember and learn from every user interaction.

Knowledge Management

Create intelligent knowledge bases that remember facts, relationships, and context.

Architecture Overview

Antigravity CLI
MCP Protocol
r3 Server
Redis(L1 Cache)
Mem0 Cloud(L2 Storage)
<5ms
Cache Hit
~200ms
Cache Miss
~10ms
First Store

Quick Example

python
from recall import RecallClient
# Initialize with simple configuration
client = RecallClient(
redis_url="redis://localhost:6379",
mem0_api_key="your-api-key"
)
# Store a memory
client.add("User prefers dark mode interfaces",
user_id="user123",
priority="high")
# Retrieve memories (served from cache if available)
memories = client.search("user interface preferences",
user_id="user123")
# Memories are automatically cached for fast access
# and persisted to cloud for reliability

Next Steps