elen — Claude Code MCP server: decision memory and setup
elen stores coding-agent decisions with their constraints and marks replaced decisions. It helps an agent look up prior choices before making a new one.
claude mcp add elen -- npx -y @learningnodes/elen-mcpWhat elen does
elen records decisions and their constraints in a graph. Its tools can search validated decisions, return brief pointers, and expand a record by ID. When a decision replaces an earlier one, elen_supersede updates the graph to reflect that change.
In local mode, records live in SQLite on your machine, with ~/.elen/decisions.db as the default path. Add the elen protocol to a rules file or system prompt so the agent checks for prior decisions before choosing and records decisions afterward. Connected mode is optional, but it requires elen login and an API key and is in beta, so using it involves extra setup.
What it helps with
- look up earlier decisions on a technical topic
- inspect a decision’s constraints by ID
- record a choice with its constraints
- mark an earlier decision as superseded
- review active decision threads at session start
Example prompts for the agent
- Search for earlier decisions about the library choice with
elen_suggest, then inspect a relevant record usingelen_expand. - Save the decision and its constraints with
elen_commit. - Show active decision threads before starting work with
elen_get_context.
How to install elen
Platform CLI
claude mcp add elen -- npx -y @learningnodes/elen-mcpPlatform CLI
codex mcp add mcp-server -- npx -y @learningnodes/elen-mcpConfig file
{
"mcpServers": {
"mcp-server": {
"command": "npx",
"args": [
"-y",
"@learningnodes/elen-mcp"
]
}
}
}Config file
{
"servers": {
"mcp-server": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@learningnodes/elen-mcp"
]
}
}
}Platform CLI
gemini mcp add mcp-server npx -y @learningnodes/elen-mcpStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about elen
How do I install elen in Claude Code?
Run claude mcp add elen -- npx -y @learningnodes/elen-mcp. This registers the MCP server under the name elen.
What does elen do?
It stores agent decisions and their constraints, searches past decisions for precedents, and marks replaced records as superseded.
Does elen require an API key?
Local mode stores data in SQLite on your machine. Connected mode requires elen login and an API key.
