MegaMemory

Persistent project knowledge graph for coding agents.

An MCP server that lets your coding agent build and query a graph of concepts, architecture, and decisions — so it remembers across sessions.

The LLM is the indexer. No AST parsing. No static analysis. Your agent reads code, writes concepts in its own words, and queries them before future tasks. The graph stores concepts — features, modules, patterns, decisions — not code symbols.

The Loop

understand → work → update

1. Session start — agent calls list_roots to orient itself
2. Before a task — agent calls understand with a natural language query (or get_concept for exact ID lookup)
3. After a task — agent calls create_concept or update_concept to record what it built

Everything persists in a per-project SQLite database at .megamemory/knowledge.db.

Installation

npm install -g megamemory

[!NOTE] Requires Node.js >= 18. The embedding model (~23MB) downloads automatically on first use.

Quick Start

megamemory install

Run the interactive installer and choose your editor:

[!NOTE] The installer only updates config files after a successful read/merge, and it will not overwrite existing plugin/command files unless they are already marked as MegaMemory-managed.

With opencode

megamemory install --target opencode

One command configures:

• MCP server in ~/.config/opencode/opencode.json
• Workflow instructions in ~/.config/opencode/AGENTS.md
• Skill tool plugin at ~/.config/opencode/tool/megamemory.ts
• Bootstrap command /user:bootstrap-memory for initial graph population
• Save command /user:save-memory to persist session knowledge

Restart opencode after running install.

With Claude Code

megamemory install --target claudecode

Configures:

• MCP server in ~/.claude.json
• Workflow instructions in ~/.claude/CLAUDE.md
• Commands in ~/.claude/commands/

With Antigravity

megamemory install --target antigravity

Configures:

• MCP server in ./mcp_config.json (workspace-level)

With Codex

megamemory install --target codex

Configures:

• MCP server in ~/.codex/config.toml
• Workflow instructions in ~/.codex/AGENTS.md

With other MCP clients

Add megamemory as a stdio MCP server. The command is just megamemory (no arguments). It reads/writes .megamemory/knowledge.db relative to the working directory, or set MEGAMEMORY_DB_PATH to override.

{
  "megamemory": {
    "type": "local",
    "command": ["megamemory"],
    "enabled": true
  }
}

MCP Tools