Groundeffect MCP Server

If you already use Groundeffect, the groundeffect mcp server is the piece that lets your assistant work with it directly. Hyper-fast, local Gmail and Google Calendar indexing for Claude Code.

What the server does

• Hybrid Search — BM25 full-text + vector semantic search with Reciprocal Rank Fusion
• Local Embeddings — Runs nomic-embed-text-v1.5 locally via Candle with Metal acceleration
• Multi-Account — Connect unlimited Gmail/GCal accounts with independent sync
• MCP Integration — Exposes email and calendar tools directly to Claude Code
• Real-time Sync — IMAP IDLE for instant email notifications, CalDAV polling for calendar
• HTML Text Extraction — Automatically converts HTML emails to clean plain text using html2text

Installation

Setup follows the usual MCP pattern — install or clone the server, register it in your client's configuration file, restart the client.

Credentials and setup notes

Configuration is passed through the environment: GROUNDEFFECT_GOOGLE_CLIENT_ID, GROUNDEFFECT_GOOGLE_CLIENT_SECRET, OPENROUTER_API_KEY, DATABASE_URL, GE_TOKEN_ENCRYPTION_KEY. Treat anything key-shaped as a real credential — scope it to the minimum the server needs, and rotate it if it ever lands in a shared config.

Where it fits

Among the team communication options, the useful question is rarely "what can it do" but "what does it cost you to run" — permissions, credentials, and how much of your context its toolset consumes. It is maintained by jamiequint; worth a glance at recent repository activity before you build anything load-bearing on it.

SyncDev reviews every entry in this directory against the project's own documentation before publishing, and revisits them as servers change.

Worth knowing first

• It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
• Missing credentials fail quietly in some clients — if no tools show up, check the environment block first.
• Keep per-call confirmation enabled while you learn its behaviour; it is the cheapest safeguard you have.