Deja Vu vs ChatCrystal

In-depth architectural comparison of the Deja Vu and ChatCrystal 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 Deja Vu 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).
• Primary tools included: Zero-dependency single binary, fully local operation, Search 3.5 GB of session history in ~1.5 ms, Supports multiple coding agents via MCP protocol.

Explore Deja Vu Details

Choose ChatCrystal 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).
• Primary tools included: Imports conversations from multiple AI coding tools, Distills conversations into notes with summaries and tags, Semantic search with embeddings and relation-aware expansion.

Feature & Specification Comparison

Specification	Deja Vu vshulcz Knowledge & Memory	ChatCrystal ZengLiangYi Knowledge & Memory
Summary	Local memory layer over the session histories coding agents already write (Claude Code, Codex CLI, opencode): lexical search, recall tools, session-start auto-recall, secret redaction at index time, cross-machine sync over SSH.	Local-first AI PKM memory server for coding conversations. Imports Claude Code, Cursor, Codex CLI, Trae, and GitHub Copilot chats into notes, semantic search, tag graphs, Markdown exports, and reusable MCP memory. npx -y chatcrystal 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": {
    "vshulcz-deja-vu": {
      "command": "npx",
      "args": [
        "-y",
        "@vshulcz/deja-vu"
      ]
    }
  }
}

{
  "mcpServers": {
    "zengliangyi-chatcrystal": {
      "command": "npx",
      "args": [
        "-y",
        "chatcrystal"
      ]
    }
  }
}

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