Memory Arbiter MCP vs Lean Memory

In-depth architectural comparison of the Memory Arbiter MCP and Lean Memory MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.

Which MCP Server Should You Choose?

Choose Memory Arbiter MCP when:

• You need dedicated capabilities in the Knowledge & Memory domain.
• You prefer remote streaming HTTP/SSE transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).
• You have access to required keys: MEMORY_ARBITER_CLIENT, MEMORY_ARBITER_AGENT_ID, MEMORY_ARBITER_MCP_TRANSPORT.
• Primary tools included: memory, memory_review, memory_govern.

Explore Memory Arbiter MCP Details

Choose Lean Memory when:

• You need dedicated capabilities in the Knowledge & Memory domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).
• You have access to required keys: LM_DATA_ROOT, ANTHROPIC_API_KEY.

Feature & Specification Comparison

Specification	Memory Arbiter MCP billy12151 Knowledge & Memory	Lean Memory Wuesteon Knowledge & Memory
Summary	AI enhancement middleware: precise retrieval replaces full-memory loading (80%+ token cut), rule-based conflict arbitration with explainable reasons, and one local SQLite shared across Claude Code/Codex/Cursor/ZCode. Local-first, zero cloud, MIT. pip install memory-arbiter-mcp	Embedded, local-first agent memory in a single SQLite file per namespace (vec0 + FTS5 hybrid retrieval). ADD-only history queryable as-of any past time; offline sleep-time maintenance stages dedupe/summarize/evict proposals a human reviews. No Docker, no server, no cloud key. pip install 'lean-memory[mcp]'
Category & Scope

Tools & Capabilities Breakdown

Ready-to-Paste Client Configurations

Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).

{
  "mcpServers": {
    "billy12151-memory-arbiter-mcp": {
      "url": "http://127.0.0.1:8000/mcp"
    }
  }
}

{
  "mcpServers": {
    "wuesteon-lean-memory": {
      "command": "uvx",
      "args": [
        "lean-memory"
      ],
      "env": {
        "LM_DATA_ROOT": "YOUR_LM_DATA_ROOT_HERE",
        "ANTHROPIC_API_KEY": "YOUR_ANTHROPIC_API_KEY_HERE"
      }
    }
  }
}

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