JMAP MCP Server vs Slack MCP Server (korotovsky)

A side-by-side comparison of two Communication servers — tools, transport, auth, maintenance, and copy-paste config for each.

	JMAP MCP Server MCP server for interacting with JMAP email servers (FastMail, Stalwart, Cyrus, James) — search, read, send, and manage email. Unverified stdio (local) API key TypeScript	Slack MCP Server (korotovsky) Powerful Slack MCP with stdio/SSE/HTTP, DMs, group DMs and no-admin token auth Verified stdio (local) API key Go
Category	Communication	Communication
Language	TypeScript	Go
Transport	stdio (local)	stdio (local)
Auth	API key	API key
GitHub stars	172	1.7k
Last commit	7 days ago	1 month ago
Verified
Actively maintained
Install	`deno run --allow-net=api.fastmail.com --allow-env=JMAP_SESSION_URL,JMAP_BEARER_TOKEN,JMAP_ACCOUNT_ID jsr:@wyattjoh/jmap-mcp@0.6.4`	`npx -y slack-mcp-server@latest --transport stdio`
Repo	Open	Open

Verdict

Pick JMAP MCP Server if you prefer its approach (mcp server for interacting with jmap email servers (fastmail, stalwart, cyrus, james) — search, read, send, and manage email).

Pick Slack MCP Server (korotovsky) if you prefer the more popular, battle-tested option, and you want a verified, documented setup.

Add JMAP MCP Server

Install / run

deno run --allow-net=api.fastmail.com --allow-env=JMAP_SESSION_URL,JMAP_BEARER_TOKEN,JMAP_ACCOUNT_ID jsr:@wyattjoh/jmap-mcp@0.6.4

Paste into ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "jmap-mcp-server": {
      "command": "deno",
      "args": [
        "run",
        "--allow-net=api.fastmail.com",
        "--allow-env=JMAP_SESSION_URL,JMAP_BEARER_TOKEN,JMAP_ACCOUNT_ID",
        "jsr:@wyattjoh/jmap-mcp@0.6.4"
      ],
      "env": {
        "JMAP_SESSION_URL": "https://api.fastmail.com/jmap/session",
        "JMAP_BEARER_TOKEN": "YOUR_API_TOKEN"
      }
    }
  }
}

Add Slack MCP Server (korotovsky)

Install / run

npx -y slack-mcp-server@latest --transport stdio

Paste into ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "slack-mcp-server-korotovsky": {
      "command": "npx",
      "args": [
        "-y",
        "slack-mcp-server@latest",
        "--transport",
        "stdio"
      ],
      "env": {
        "SLACK_MCP_XOXP_TOKEN": "<your-slack-user-oauth-token-xoxp>"
      }
    }
  }
}

FAQ

JMAP MCP Server or Slack MCP Server (korotovsky) — which is better?

Pick JMAP MCP Server if you prefer its approach (mcp server for interacting with jmap email servers (fastmail, stalwart, cyrus, james) — search, read, send, and manage email). Pick Slack MCP Server (korotovsky) if you prefer the more popular, battle-tested option, and you want a verified, documented setup.

Can I use both JMAP MCP Server and Slack MCP Server (korotovsky)?

Yes — MCP clients let you enable multiple servers at once. Add both configs to your client's mcpServers and use whichever tool fits the task.

Do JMAP MCP Server and Slack MCP Server (korotovsky) work with Claude, Cursor and Windsurf?

Both do. Copy the per-client config below into Claude Desktop, Cursor, or Windsurf.

View JMAP MCP Server →View Slack MCP Server (korotovsky) →More comparisons →