Mantle

Mantle is a self-hosted, open-source AI memory system that ingests your emails, files, notes, conversations, contacts, and calendar into a structured knowledge base you own. Unlike typical AI assistants that wait for a question and forget everything after the chat ends, Mantle runs autonomously in the background. It reads your inbox while you sleep, files receipts, surfaces forgotten items, and sends a morning briefing without you ever opening the app. It runs on your own hardware, so your data stays yours.

The core of Mantle is a six-layer memory architecture: a persona layer that learns how you like to be helped, recent turns for live conversation, digests that compress older chats by topic, profile facts that keep durable truths current, a content index with summaries and vectors for search, and an append-only content store for original documents. On top of that sits a knowledge graph that extracts relationships automatically, and a lossless recall system that can replay the exact words of any past conversation. The assistant shows a live thought trail as it works, streaming replies token by token, and you can stop a turn mid-sentence. It also supports MCP (Model Context Protocol) with 149 tools for search, graph, pages, tables, files, email, and tool authoring, plus a built-in API console.

Mantle is built for anyone who wants a persistent, autonomous AI assistant that actually knows their life or work. Individuals can use it to manage personal information across email, files, and notes. Teams can hand colleagues a token for read-only access to shared knowledge, with change requests landing in a review queue and full audit logging. For larger organizations, multiple Mantle instances can be federated so each department keeps its own sovereign brain while questions route to the one that holds the answer. The tool is open source and designed to be safe to leave running, treating all ingested data as data rather than instructions to prevent prompt injection atta...