# GBrain

> Garry Tan's open-source agent brain: shared memory with sources, corrections and a knowledge graph, served to Claude, Codex, OpenClaw, Hermes and others over MCP.

- id: `gbrain`
- category: Tools (`tools`)
- url: https://github.com/garrytan/gbrain
- repo: https://github.com/garrytan/gbrain
- status: active
- pricing: open-source
- license: MIT
- tags: memory, knowledge-graph, mcp, personal-agent, self-hosted, typescript
- llms.txt: https://raw.githubusercontent.com/garrytan/gbrain/master/llms.txt
- auth: other
- access notes: Local brains need no key; remote/hosted brains use OAuth or a private machine connection (see docs/guides/hosted-harness-access.md). Hosted option: https://gbrain.io
- related: memU (https://indexagentica.com/entries/memu/); Mem0 (https://indexagentica.com/entries/mem0/); Basic Memory (https://indexagentica.com/entries/basic-memory/); Honcho (https://indexagentica.com/entries/honcho/); OpenClaw (https://indexagentica.com/entries/openclaw/); Hermes Agent (https://indexagentica.com/entries/hermes-agent/)
- sources: https://github.com/garrytan/gbrain , https://gbrain.io
- added: 2026-10-23
- updated: 2026-10-23
- last verified: 2026-10-23
- maintainer: Garry Tan
- submitted by: agentica-curator
- page: https://indexagentica.com/entries/gbrain/
- json: https://indexagentica.com/api/entries/gbrain.json

GBrain stores explicit facts with provenance, supports corrections and withdrawal, and makes the same memory available across agents. Start keyless with keyword retrieval, then add semantic search, a cited synthesis layer (answers with an explicit note on what the brain doesn't know), a typed knowledge graph and background enrichment/consolidation jobs. Connects to coding agents and personal agents over MCP; `gbrain mcp expose` publishes a local brain on a Tailscale tailnet (with `--funnel` for cloud agents). Install requires Bun ≥1.4 via `bun install -g github:garrytan/gbrain`; the README warns that the npm package named `gbrain` is unrelated. A hosted team version is offered at gbrain.io. Ships llms.txt, llms-full.txt and AGENTS.md for agents.