Introduction

What is MemLib?

MemLib is an open-source memory API that gives your AI agents persistent, semantic memory. Store natural language, and MemLib automatically extracts facts, deduplicates, resolves conflicts, and retrieves memories by meaning — all via a simple SDK or REST API.

Bring Your Own Database. Your memory data stays in your PostgreSQL instance. MemLib connects to your database and AI provider at request time — no vendor lock-in, full data ownership.

Key Capabilities

Capability	What It Does	LLM Calls
Smart Store	Extract facts from natural language, deduplicate, and resolve conflicts	1–2
Semantic Recall	Find memories by meaning with hybrid scoring	0
Context Synthesis	Synthesize a tailored briefing paragraph for your system prompt	2
Memory Diff	Track what changed — new facts, updates, and contraditions	0
Consolidation	Summarize old memories into concise entries	1
MCP Server	Let Claude, Cursor, and other clients use memories directly	—

How It Works

Supported Providers

LLM: Google Gemini · OpenAI · Anthropic · Mistral · Groq · xAI · Cohere · OpenRouter

Embedding: Google Gemini · OpenAI · Cohere · Mistral · Voyage

Architecture

Component	Description
SDK (`memlib` on npm)	TypeScript client with typed methods
REST API	HTTP endpoints with API key auth
MCP Server	Model Context Protocol for Claude Desktop, Cursor, etc.
Memory Engine	Embedding, fact extraction, dedup, conflict resolution
Dashboard	Web UI for project management, API keys, and memory browsing

Quick Example

import { MemLib } from "memlib";

const mem = new MemLib({
  apiKey: "sk_...",
  namespace: "my-app",
  entity: "user-123",
});

// Store — extracts facts, deduplicates, resolves conflicts
await mem.store({
  content: "I prefer TypeScript and dark mode. My team uses React.",
});

// Recall — semantic search by meaning
const memories = await mem.recall({
  query: "What tech stack?",
});

// Prepare — synthesize context for a system prompt
const { context } = await mem.prepare({
  messages: [{ role: "user", content: "Help me set up a project" }],
});

// Diff — what changed since last session
const diff = await mem.diff({ since: "2024-01-01T00:00:00Z" });

Next Steps

Quickstart — get up and running in 5 minutes
How It Works — architecture and data model
SDK Reference — full method documentation
MCP Guide — connect to Claude Desktop or Cursor