All tools / MCP memory server

MCP Memory (official reference server)

Knowledge-graph memory (entities, relations, observations) stored in a local JSONL file. The reference implementation many forks build on.

Works with

Claude DesktopVS Code / Copilot

Per vendor docs, checked 2026-11-09. Not tested by MemoryStack. Source

Install

npx -y @modelcontextprotocol/server-memory

Or add it to every detected agent with add-mcp:

npx add-mcp @modelcontextprotocol/server-memory

From the vendor's docs. Read them before running anything.

Details

Runs
Runs locally
MCP transport
stdio
Auth
None (local process)
Storage
JSONL file
License
MIT / Apache-2.0 (relicensing in progress)
GitHub
modelcontextprotocol/servers/src/memory
Stars
91,894 (whole repo)
Last release
None published / not tracked
Last push
2026-11-05
Archived
No
Website
modelcontextprotocol.io

Known pitfalls

  • Two server processes sharing one MEMORY_FILE_PATH silently discard each other's writes (the in-process mutex does not span processes) Source
  • MEMORY_FILE_PATH ignored in older versions; memory.json landed in the npx temp directory Source

Change history

  • Added to MemoryStack.
  • Issue #4797 (two processes sharing MEMORY_FILE_PATH lose writes) closed. Link