Perseus Vault vs Lean Memory

In-depth architectural comparison of the Perseus Vault 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 Perseus Vault 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: PERSEUS_VAULT_ENCRYPTION_KEY.
• Primary tools included: Single Rust binary with embedded SQLite, AES-256-GCM encryption at rest, Hybrid BM25 full-text and dense vector search.

Explore Perseus Vault 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	Perseus Vault Perseus-Computing-LLC Knowledge & Memory	Lean Memory Wuesteon Knowledge & Memory
Summary	Local-first, MCP-native persistent memory for AI agents — a single Rust binary with embedded SQLite, hybrid FTS5 + dense-vector search, and optional AES-256-GCM encryption. Fully offline, no cloud.	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": {
    "perseus-computing-llc-perseus-vault": {
      "command": "npx",
      "args": [
        "-y",
        "perseus-computing-llc-perseus-vault"
      ],
      "env": {
        "PERSEUS_VAULT_ENCRYPTION_KEY": "YOUR_PERSEUS_VAULT_ENCRYPTION_KEY_HERE"
      }
    }
  }
}

{
  "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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