pg-agent-memory

pg-agent-memory

Stateful AI agent memory layer for PostgreSQL with pgvector. TypeScript-first with intelligent context management and semantic search.

Why pg-agent-memory?

The Problem: AI Agents Forget Everything

❌ Without pg-agent-memory

// Day 1: User shares preference
await openai.chat.completions.create({
  messages: [{ role: 'user', content: 'I prefer Python' }],
});
// AI: "Got it! I'll remember that."

// Day 2: User asks for help
await openai.chat.completions.create({
  messages: [{ role: 'user', content: 'Help me start a project' }],
});
// AI: "What language would you like to use?"
// 😤 Forgot everything!

✅ With pg-agent-memory

// Day 1: Store preference
await memory.remember({
  conversation: userId,
  content: 'User prefers Python',
  role: 'system',
});

// Day 2: Retrieve context
const context = await memory.getHistory(userId);
await openai.chat.completions.create({
  messages: [...context, { role: 'user', content: 'Help me start a project' }],
});
// AI: "I'll create a Python project for you!"
// 🎯 Remembers everything!

Features

• Persistent Memory - Conversations continue across sessions
• Multi-Model Support - OpenAI, Anthropic, DeepSeek, Google, Meta + custom providers
• Local Embeddings - Zero API costs for vector embeddings with Sentence Transformers
• Memory Compression - Automatic summarization with 4 compression strategies
• Semantic Search - Find relevant memories using AI embeddings
• Universal Tokenizer - Accurate token counting based on official provider documentation
• TypeScript First - Full type safety with autocomplete
• PostgreSQL Native - Uses your existing database
• Zero-Cost Embeddings - Local Sentence Transformers (@xenova/transformers)
• High Performance - ~9ms memory operations, ~5ms vector search

Coming Soon

• Multi-agent memory sharing
• Memory graph visualization
• Pattern detection

Quick Start

# Install
npm install pg-agent-memory

# Start PostgreSQL with Docker (includes pgvector)
docker compose up -d

# Run example
npm start

Installation

npm install pg-agent-memory

Database Setup

Option 1: Docker (Recommended)

# Use included docker compose configuration
docker compose up -d

Option 2: Existing PostgreSQL

-- Enable pgvector extension
CREATE EXTENSION IF NOT EXISTS vector;

Basic Usage

import { AgentMemory } from 'pg-agent-memory';

// Option 1: Static factory method (recommended)
const memory = await AgentMemory.create({
  agent: 'my-assistant',
  connectionString: 'postgresql://user:pass@localhost:5432/db',
});

// Option 2: Traditional constructor + initialize
const memory = new AgentMemory({
  agent: 'my-assistant',
  connectionString: 'postgresql://user:pass@localhost:5432/db',
});
await memory.initialize();

// Store conversation memory
const memoryId = await memory.remember({
  conversation: 'user-123',
  content: 'User prefers email notifications',
  role: 'user',
  importance: 0.8,
  timestamp: new Date(),
});

// Find related memories using vector similarity
const related = await memory.findRelatedMemories(memoryId, 5);

// Semantic search across memories
const relevant = await memory.searchMemories('notification preferences');

// Get relevant context for a query
const context = await memory.getRelevantContext(
  'user-123',
  'user communication preferences',
  1000 // max tokens
);

console.log(`Found ${context.messages.length} relevant memories`);
console.log(`Relevance score: ${context.relevanceScore}`);

// Health check for monitoring
const health = await memory.healthCheck();
console.log(`Status: ${health.status}, Memories: ${health.details.memoryCount}`);

// Cleanup
await memory.disconnect();

Multi-Model Support

Configure multiple AI providers with accurate token counting and prompt caching:

const memory = new AgentMemory({
  agent: 'multi-model-bot',
  connectionString,
  modelProviders: [
    {
      name: 'gpt-4o',
      provider: 'openai',
      model: 'gpt-4o',
      tokenLimits: { context: 128000, output: 4000 },
      // High context limit: Supports large conversations
    },
    {
      name: 'claude-sonnet',
      provider: 'anthropic',
      model: 'claude-sonnet-4-20250514',
      tokenLimits: { context: 200000, output: 4000 },
      // Large context window: Perfect for long conversations
    },
    {
      name: 'deepseek-coder',
      provider: 'deepseek',
      model: 'deepseek-coder',
      tokenLimits: { context: 32000, output: 4000 },
      // Cost-effective option for coding tasks
    },
    {
      name: 'gemini-pro',
      provider: 'google',
      model: 'gemini-1.5-pro',
      tokenLimits: { context: 1048576, output: 8192 },
      // Massive context window: Handle very long conversations
    },
    {
      name: 'llama-3',
      provider: 'meta',
      model: 'llama-3.1-70b',
      tokenLimits: { context: 128000, output: 4000 },
      // More efficient tokenizer: ~44% fewer tokens than OpenAI
    },
  ],
  defaultProvider: 'gpt-4o',
  tokenCountingStrategy: 'hybrid', // 'precise', 'fast', or 'hybrid'
});

// Token counting uses official provider documentation:
// - OpenAI: ~4 chars/token or 0.75 words/token (official baseline)
// - Anthropic: ~3.5 chars/token (14% more tokens)
// - DeepSeek: ~3.3 chars/token (20% more tokens)
// - Google: ~4 chars/token (same as OpenAI)
// - Meta/Llama: ~0.75 tokens/word (44% fewer tokens - more efficient)
await memory.remember({
  conversation: userId,
  content: longText,
  provider: 'gpt-4o', // Use OpenAI for this memory
});

Memory Compression

Automatic memory compression with multiple strategies:

// Enable compression for large conversations
const compressionResult = await memory.compressMemories({
  strategy: 'hybrid', // 'token_based', 'time_based', 'importance_based', 'hybrid'
  maxAge: '7d',
  targetCompressionRatio: 0.6,
});

console.log(`Compressed ${compressionResult.memoriesCompressed} memories`);
console.log(`Token savings: ${compressionResult.tokensSaved}`);

// Get context with automatic compression
const context = await memory.getRelevantContextWithCompression(
  'coding preferences',
  4000 // Automatically compresses if needed
);

Real-World Integration

With OpenAI

import OpenAI from 'openai';
import { AgentMemory } from 'pg-agent-memory';

const client = new OpenAI({
  apiKey: process.env.OPENAI_API_KEY,
});

const memory = new AgentMemory({ agent: 'support-bot', connectionString });

// Retrieve conversation history
const history = await memory.getHistory(userId);

// Include memory in AI request
const completion = await client.chat.completions.create({
  model: 'gpt-4o',
  messages: [
    ...history.map(m => ({ role: m.role, content: m.content })),
    { role: 'user', content: userMessage },
  ],
});

// Store the interaction
await memory.remember({
  conversation: userId,
  content: userMessage,
  role: 'user',
  importance: 0.5,
  timestamp: new Date(),
});

await memory.remember({
  conversation: userId,
  content: completion.choices[0].message.content,
  role: 'assistant',
  importance: 0.7,
  timestamp: new Date(),
});

With Anthropic Claude

import Anthropic from '@anthropic-ai/sdk';
import { AgentMemory } from 'pg-agent-memory';

const client = new Anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY,
});

const memory = new AgentMemory({
  agent: 'claude-assistant',
  connectionString,
  modelProviders: [
    {
      name: 'claude',
      provider: 'anthropic',
      model: 'claude-sonnet-4-20250514',
      tokenLimits: { context: 200000, output: 4000 },
    },
  ],
});

// Get conversation with compression for large contexts
const context = await memory.getRelevantContextWithCompression(
  'user preferences and history',
  180000 // Near Claude's context limit
);

const message = await client.messages.create({
  model: 'claude-sonnet-4-20250514',
  max_tokens: 1024,
  messages: [
    ...context.messages.map(m => ({ role: m.role, content: m.content })),
    { role: 'user', content: userMessage },
  ],
});

// Store the interaction
await memory.remember({
  conversation: userId,
  content: message.content[0].text,
  role: 'assistant',
  importance: 0.7,
  timestamp: new Date(),
});

With Vercel AI SDK

import { streamText } from 'ai';
import { openai } from '@ai-sdk/openai';
import { AgentMemory } from 'pg-agent-memory';

const memory = new AgentMemory({ agent: 'chat-assistant', connectionString });

export async function POST(req: Request) {
  const { messages, userId } = await req.json();

  // Get user's conversation history
  const history = await memory.getHistory(userId);

  const result = streamText({
    model: openai('gpt-4o'),
    system: 'You are a helpful assistant with memory.',
    messages: [...history, ...messages],
  });

  // Store the conversation
  for (const message of messages) {
    await memory.remember({
      conversation: userId,
      role: message.role,
      content: message.content,
      importance: 0.5,
      timestamp: new Date(),
    });
  }

  return result.toDataStreamResponse();
}

API Reference

AgentMemory

Static Methods

AgentMemory.create(config: MemoryConfig): Promise<AgentMemory>

Recommended: Creates and initializes an AgentMemory instance in one call.

const memory = await AgentMemory.create({
  agent: 'my-bot',
  connectionString: 'postgresql://...',
});

Constructor

new AgentMemory(config: MemoryConfig)

MemoryConfig:

• agent: string - Unique agent identifier
• connectionString: string - PostgreSQL connection string
• tablePrefix?: string - Table prefix (default: 'agent')
• maxTokens?: number - Max tokens per memory (default: 4000)
• embeddingDimensions?: number - Vector dimensions (default: 384)

Core Methods

initialize(): Promise<void>

Initialize database schema and embedding model.

remember(message: Message): Promise<string>

Store a conversation memory.

findRelatedMemories(memoryId: string, limit?: number): Promise<Message[]>

Find memories related to a specific memory using vector similarity.

const related = await memory.findRelatedMemories(memoryId, 5);

healthCheck(): Promise<HealthStatus>

Check system health for monitoring and debugging.

const health = await memory.healthCheck();
// Returns: { status: 'healthy' | 'unhealthy', details: {...} }

Message:

{
  conversation: string;    // Conversation ID
  content: string;         // Memory content
  role: 'user' | 'assistant' | 'system'; // Required, defaults to 'user'
  importance: number;      // 0-1 relevance score, defaults to 0.5
  timestamp: Date;         // Required, defaults to new Date()
  id?: string;             // Optional memory ID
  metadata?: Record<string, unknown>;
  embedding?: number[];    // Optional vector embedding
  expires?: Date | string; // Expiration (e.g., '30d', '1h')
}

recall(filter: MemoryFilter): Promise<Context>

Retrieve memories with filtering.

getHistory(conversation: string, limit?: number): Promise<Message[]>

Get chronological conversation history.

getRelevantContext(conversation: string, query: string, maxTokens: number): Promise<Context>

Find semantically relevant memories for a query.

searchMemories(query: string, filters?: MemoryFilter): Promise<Message[]>

Semantic search across all agent memories.

deleteMemory(memoryId: string): Promise<void>

Delete specific memory.

deleteConversation(conversation: string): Promise<void>

Delete entire conversation.

Database Requirements

• PostgreSQL 12+
• pgvector extension

Performance

• Memory operations: ~9ms average (range: 5-22ms, first operation slower due to model loading)
• Vector search: ~5ms average for semantic similarity search using pgvector
• Token counting: <1ms sub-millisecond performance for all text sizes
• Embedding generation: Local processing, no API calls required
• Model size: ~80-90MB (all-MiniLM-L6-v2, cached after first download)
• Architecture: Built for production scale with proper indexing and connection pooling

Architecture

┌─────────────────┐    ┌──────────────────┐    ┌─────────────────┐
│   AgentMemory   │────│  EmbeddingService │────│ @xenova/trans.. │
│                 │    │                  │    │   (Local Model) │
└─────────────────┘    └──────────────────┘    └─────────────────┘
         │
         ▼
┌─────────────────┐    ┌──────────────────┐
│   PostgreSQL    │────│     pgvector     │
│   (Memories)    │    │  (Vector Search) │
└─────────────────┘    └──────────────────┘

Components:

• AgentMemory: Main API for memory operations
• EmbeddingService: Local text-to-vector conversion using @xenova/transformers
• PostgreSQL: Persistent storage with ACID properties
• pgvector: Efficient vector similarity search
• @xenova/transformers: Local Sentence Transformers model (all-MiniLM-L6-v2)

Examples

Chatbot Integration

import { AgentMemory } from 'pg-agent-memory';

class ChatBot {
  private memory: AgentMemory;

  constructor() {
    this.memory = new AgentMemory({
      agent: 'chatbot',
      connectionString: process.env.DATABASE_URL,
    });
  }

  async processMessage(userId: string, message: string) {
    // Store user message
    await this.memory.remember({
      conversation: userId,
      content: message,
      role: 'user',
      importance: 0.5,
      timestamp: new Date(),
    });

    // Get relevant context
    const context = await this.memory.getRelevantContext(userId, message, 800);

    // Generate response using context
    const response = await this.generateResponse(message, context);

    // Store bot response
    await this.memory.remember({
      conversation: userId,
      content: response,
      role: 'assistant',
      importance: 0.7,
      timestamp: new Date(),
    });

    return response;
  }
}

Advanced Filtering

// Search with filters
const memories = await memory.searchMemories('user preferences', {
  importance: { min: 0.7 },
  dateRange: {
    start: new Date('2024-01-01'),
    end: new Date('2024-12-31'),
  },
  metadata: { category: 'user_settings' },
  limit: 10,
});

// Get memories by role
const userMessages = await memory.recall({
  conversation: 'user-123',
  role: 'user',
  limit: 50,
});

Running Examples

# Set database URL
export DATABASE_URL="postgresql://user:pass@localhost:5432/dbname"

# Run basic example
npm run example:basic

# Run chatbot example
npm run example:chatbot

# Run all examples
npm run example:all

Development

Quick Start with Docker

# Clone repository
git clone <repository>
cd pg-agent-memory
npm install

# Start PostgreSQL with pgvector
npm run dev:up

# Copy environment variables
cp .env.example .env

# Run examples
npm run example:basic

# Run tests
npm run test:docker

Docker Commands

# Start development database
npm run dev:up

# Stop database (data persists)
npm run dev:down

# View database logs
npm run dev:logs

# Clean everything (including data)
npm run dev:clean

# Connect to PostgreSQL shell
bash scripts/docker-dev.sh shell

Manual Setup

If you prefer using your own PostgreSQL:

# Install pgvector extension
CREATE EXTENSION IF NOT EXISTS vector;

# Set connection string
export DATABASE_URL="postgresql://user:pass@localhost:5432/dbname"

# Run tests
npm test
npm run test:integration

Testing

# Unit tests (no database needed)
npm test

# Integration tests with Docker
npm run test:docker

# Integration tests with custom database
export DATABASE_URL="postgresql://user:pass@localhost:5432/test_db"
npm run test:integration

# All tests
npm run test:all

# Code quality checks
npm run lint           # ESLint + Prettier
npm run type-check     # TypeScript compilation
npm run validate       # Full validation (lint + type-check + tests)

# Performance benchmarks
npm run benchmark      # Verify performance claims

License

MIT © Alex Potapenko

Contributing

• Fork the repository
• Create a feature branch
• Run tests: npm test
• Submit a pull request

Support

• GitHub Issues
• Documentation