--- title: "Knowledge Graph Memory reference server: review, setup & limitations · Undominated.ai" canonical: https://undominated.ai/mcp-servers/memory/ description: "Persist named entities, observations and relations in a local JSONL graph between client sessions." --- # Knowledge Graph Memory reference server: review, setup & limitations · Undominated.ai > Persist named entities, observations and relations in a local JSONL graph between client sessions. [← Explore all mcp servers](/mcp-servers/) WORKSPACE KNOWLEDGE / Model Context Protocol steering group # Knowledge Graph Memory reference server Persist named entities, observations and relations in a local JSONL graph between client sessions. See setup guidance ↓Original source ↗ SOURCE REVIEW Reviewed 2026-09-21 Evidence 5 linked sources Publisher Model Context Protocol steering group Licence Apache-2.0 / MIT transition; documentation CC-BY-4.0 ↗ Revision d73f99efbfd4 Read what was—and wasn’t—checked ↓ “A basic implementation of persistent memory using a local knowledge graph.” Model Context Protocol steering group · upstream description ↗ Our analysis follows below. 01 / THE REASONING ## Why this made the selection. - Keeps a small, inspectable local graph without requiring a vector database or service account. - Explicit entity, observation and relation tools make memory writes and deletions visible. ### A good fit for - Prototype persistent project or personal context. - Inspect and edit a compact graph through an MCP client. ### Weigh up before choosing - The publisher describes this as an educational reference implementation, not a production-ready service. - Memory is stored as plain JSONL, and read_graph returns the full graph to the client. Choose carefully what the agent may persist. - The implementation serializes mutations inside one process; cross-process coordination was not established. 02 / THE REVIEW RECORD ## What we actually inspected. Source review has boundaries. A clear record is more useful than a “safe” badge. ### Material inspected - src/memory/README.md, package.json and index.ts. - Storage path configuration, graph read/write and delete handlers, resource notifications and stdio startup. - Repository licence transition. ### Our findings - Writes use a same-directory temporary file and rename, which reduces partial-file replacement risk on POSIX systems. - The server can remove entities and their relations. Persistence does not verify the truth of a saved observation. ### Not established by this review - Server launch, authenticated tool calls, and release-to-source parity were not tested. The review applies to the material and revision named here. A newer upstream release can change its behavior. 03 / PUT IT TO WORK ## Connect a server deliberately. Upstream setup instructions ↗ DOCUMENTED COMMAND npx -y @modelcontextprotocol/server-memory Copy command ↗ Copying does not execute this command. It may retrieve a newer version than the reviewed source. - Configure the documented npx command in a stdio client. - Set MEMORY_FILE_PATH to a persistent file location under your control rather than relying on the package-directory default. - Review the client’s memory instructions, stored content, backup policy and access permissions. ### Before you start - Node.js and npm/npx. - A writable directory for the memory file. ### Documented configuration example Use the client and authentication context described in the setup guidance. Configuration formats vary between hosts. { "mcpServers": { "memory": { "command": "npx", "args": [ "-y", "@modelcontextprotocol/server-memory" ], "env": { "MEMORY_FILE_PATH": "/path/to/custom/memory.jsonl" } } } } Copy configuration ↗ ### Compatibility Claude Desktop · VS Code · stdio clients ### Implementation TypeScript ### Transports stdio ### Local process - Reads and changes a local graph file. - Returns stored personal or project information to the connected client; the client may send it to its model provider. ### Cost model Runs on your machine; hosting and any connected model client are separate costs. 04 / FOLLOW THE EVIDENCE ## The source trail. Our notes are separate from the original resource. Check upstream before adopting a new version. - Knowledge Graph Memory reference server setup and scope ↗ Checked 2026-09-21 https://raw.githubusercontent.com/modelcontextprotocol/servers/d73f99efbfd40c3aa1b61e88728b3d49fb52608f/src/memory/README.md Supports: summary, upstreamDescription, whySelected, bestFor, limitations, install, access, compatibility, transports, review - MCP steering-group reference implementation scope ↗ Checked 2026-09-21 https://raw.githubusercontent.com/modelcontextprotocol/servers/d73f99efbfd40c3aa1b61e88728b3d49fb52608f/README.md Supports: publisher, upstreamDescription, limitations, review - Current MCP repository licence transition ↗ Checked 2026-09-21 https://raw.githubusercontent.com/modelcontextprotocol/servers/d73f99efbfd40c3aa1b61e88728b3d49fb52608f/LICENSE Supports: license, review - Memory package and executable ↗ Checked 2026-09-21 https://raw.githubusercontent.com/modelcontextprotocol/servers/d73f99efbfd40c3aa1b61e88728b3d49fb52608f/src/memory/package.json Supports: language, install - Memory storage and tool implementation ↗ Checked 2026-09-21 https://raw.githubusercontent.com/modelcontextprotocol/servers/d73f99efbfd40c3aa1b61e88728b3d49fb52608f/src/memory/index.ts Supports: review, limitations, access, transports KEEP COMPARING ## Other approaches to consider. Related by category or shared topics. These are alternatives to inspect, not a measured quality order. [### Atuin MCP ↗ Let an agent search your shell history and retrieve captured command output without executing those commands.](/mcp-servers/atuin/)[### Notion MCP ↗ Searches and edits a Notion workspace through user-authorized remote tools, with plan-dependent access to connected-source search.](/mcp-servers/notion/)[### Fetch MCP reference server ↗ Retrieve a URL as text or Markdown in chunks through a small local MCP server.](/mcp-servers/fetch/) [AI Tools ↗](/tools/)[Skills ↗](/skills/)[Agents ↗](/agents/)[MCP Servers ↗](/mcp-servers/)