Elen

Elen is an open-source MCP server that records the decisions your coding agent makes, with the limits that bound them, and marks old decisions as superseded. It installs with one npx line, works with Cursor, Claude Code and any MCP client, and keeps decisions in a local SQLite file.

Install

npx -y @learningnodes/elen-mcp@0.3.1

Claude Code

claude mcp add --transport stdio elen -- npx -y @learningnodes/elen-mcp@0.3.1

VS Code

Open this link to install:

vscode:mcp/install?%7B%22name%22%3A%22elen%22%2C%22command%22%3A%22npx%22%2C%22args%22%3A%5B%22-y%22%2C%22%40learningnodes%2Felen-mcp%400.3.1%22%5D%7D

Cursor

Add this to .cursor/mcp.json in your project:

{

"mcpServers": { "elen": { "command": "npx", "args": ["-y", "@learningnodes/elen-mcp@0.3.1"] } } }

Gemini CLI

Add this to settings.json (~/.gemini/settings.json, or .gemini/settings.json in your project):

{

"mcpServers": { "elen": { "command": "npx", "args": ["-y", "@learningnodes/elen-mcp@0.3.1"] } } }

Any other MCP client

Use the same mcpServers entry:

{

"mcpServers": { "elen": { "command": "npx", "args": ["-y", "@learningnodes/elen-mcp@0.3.1"] } } }

Tested with

Make your agent use it

The tools alone give an agent no habit: it sees what each tool does, but it does not stop mid-task to ask whether a precedent exists. Add the block below to your rules file or system prompt so that searching before a decision and committing after one become part of every session.

# Epistemic Decision Memory Protocol

You must adhere to the Minimal Token Protocol for decisions:

1. Pointer-First Retrieval: Before making a technical decision, ALWAYS use elen_suggest to retrieve Top-K minimal pointers.
2. On-Demand Expansion: If a pointer looks relevant, you MUST call elen_expand on that specific ID. Do not hallucinate constraints.
3. Commiting Atoms: When deciding, use elen_commit. Summarize constraints into plain-text arrays (e.g. "budget < 500ms").
4. Graph Revision: If a decision invalidates a precedent, you MUST use elen_supersede to advance the graph state.

What it stores

In local mode decisions stay in a SQLite file on your machine (default ~/.elen/decisions.db). Connected mode is optional, needs elen login and an API key, and is in beta.

Tools

Links

• Repository: https://github.com/LearningNodes/Elen
• Issues: https://github.com/LearningNodes/Elen/issues
• Discord: https://discord.gg/zJG6n2WGzM
• Licence: AGPL-3.0

Elen is the open-source part of Learning Nodes, the DecisionOps workspace. For the business decisions behind the code: https://workstation.learningnodes.com?utm_source=elen-readme&utm_medium=referral&utm_campaign=npm-page