MemPalace is an open-source tool that stores and retrieves verbatim conversation history on your machine using semantic search and a pluggable vector-store backend. It supports ChromaDB, SQLite exact vectors, Qdrant, and pgvector, and ships a CLI and Docker images for easy setup without external APIs. Benchmarks show 96.6% recall at top-5 on LongMemEval with zero cloud or LLM calls.

Stash is an open-source service that adds continuous memory to any AI model by storing and organizing session data in PostgreSQL with pgvector. It transforms raw conversations into structured facts, relationships, and patterns, so agents recall preferences, avoid repeated errors, and track long-term goals. Integration via MCP makes it model-agnostic, self-hostable, and free of vendor lock-in.

Stash lets your AI agent keep memory across conversations, so you don’t have to repeat context every time. It’s an open-source, self-hosted layer that uses Postgres, pgvector, and an eight-stage consolidation pipeline to turn raw observations into structured knowledge. It plugs into any MCP-compatible agent with a single Docker command.