Federated messaging with your fmsg hosting provider. Connect with OAuth or an API key.
To add fmsg to Claude, run the install command below or copy the ready-made config for Claude Code, Claude Desktop, Cursor and VS Code further down. Restart your client after adding it and its tools show up in your next conversation. It needs 4 environment variables, listed below.
Install
npx -y @markmnl/fmsg-mcp@1.4.0Environment variables
FMSG_API_URLSet in your MCP configFMSG_API_KEYSet in your MCP configFMSG_DEFAULT_DOMAINSet in your MCP configFMSG_MCP_DOWNLOAD_DIRSet in your MCP configInstall with your client
claude mcp add fmsg --env FMSG_API_URL=<YOUR_FMSG_API_URL> --env FMSG_API_KEY=<YOUR_FMSG_API_KEY> --env FMSG_DEFAULT_DOMAIN=<YOUR_FMSG_DEFAULT_DOMAIN> --env FMSG_MCP_DOWNLOAD_DIR=<YOUR_FMSG_MCP_DOWNLOAD_DIR> -- npx -y @markmnl/fmsg-mcp@1.4.0
Run this in a terminal to add the server to Claude Code.
What this does
fmsg exposes a set of tools to Claude over the Model Context Protocol. After you add it to claude_desktop_config.json (snippet above) and restart Claude Desktop, those tools become callable inside any conversation.
Requirements
This server needs the following environment variables to be set before it can run:
FMSG_API_URL FMSG_API_KEY FMSG_DEFAULT_DOMAIN FMSG_MCP_DOWNLOAD_DIR
Set these via the env object in your MCP config (see claude_desktop_config.json snippet above).
Frequently asked questions
How do I install fmsg?
Run the Claude Code command in the install section to add fmsg to Claude Code, or copy the ready-made config for your client from the install section on this page. Restart your client afterwards and the tools appear in your next conversation.
Which clients work with fmsg?
This page carries setup and config for Claude Code, Claude Desktop, Cursor and VS Code. Any other MCP client that accepts a standard server config can connect to fmsg as well.
Does fmsg need an API key?
Yes. Before it can run, set these environment variables: FMSG_API_URL, FMSG_API_KEY, FMSG_DEFAULT_DOMAIN, FMSG_MCP_DOWNLOAD_DIR. They go in the env block of your MCP config.
Imported from the Official MCP Registry. The details above come from the registry entry; the maker can claim this listing to correct them, add docs, and see its traffic.
Is this your MCP server?
Claim this listing to see its traffic, fix details yourself, and skip the review queue on future updates.
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