# Engram

> Persistent knowledge base MCP server with full-text search and graph relations.

Engram is an open-source Model Context Protocol (MCP) server that gives AI agents persistent memory. Entries are plain Markdown files with YAML frontmatter. The search index is a rebuildable cache with a pluggable backend (Xapian by default).

## Tools

- remember: Store or update knowledge (upsert with smart duplicate detection)
- recall: Read an entry with its graph relations (outgoing + backlinks)
- search: Full-text search with pluggable backend and tag filtering
- forget: Remove an entry
- list: Browse entries by tag
- tags: List all tags with counts
- rebuild: Rebuild search index from files

## Graph Relations

Entries can link to each other using `kb://uuid#type` URLs in Markdown content. The #type fragment (e.g. runs-on, depends-on, mirrors) defines the relation kind. recall returns both outgoing links and incoming backlinks — like HATEOAS for knowledge.

## Quick Start

```bash
docker run -i -v ./knowledge:/knowledge cylian/engram
```

## Links

- Website: https://engram-kb.org
- GitHub: https://github.com/cylian-org/engram
- Docker Hub: https://hub.docker.com/r/cylian/engram
- License: MIT