Calendar MCP Server

@chronary/mcp

MCP server for Chronary — calendar tools for AI assistants.

Drops 50 calendar tools (manage agents, calendars, and events, request human Google/Microsoft setup, find meeting times, run scheduling proposals, configure availability rules, manage webhooks, iCal subscriptions, scoped keys, audit log, and usage) into any MCP-compatible client: Claude Desktop, Cursor, VS Code Copilot, Claude Code, Windsurf.

One-click install via Smithery: npx -y @smithery/cli mcp add chronary/agent-calendar --client claude (swap --client for cursor, vscode, claude-code, windsurf, …).

Prerequisites

1. A Chronary account — sign up at chronary.ai.
2. An API key from the console (starts with chr_sk_).
3. Node.js ≥ 18 on the machine where the MCP client runs.

Client configurations

All examples use npx -y @chronary/mcp, which downloads and runs the latest version on demand. No install step required.

Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

macOS / Linux:

{
  "mcpServers": {
    "chronary": {
      "command": "npx",
      "args": ["-y", "@chronary/mcp"],
      "env": {
        "CHRONARY_API_KEY": "chr_sk_..."
      }
    }
  }
}

Windows (uses cmd /c because spawn can't resolve npx.cmd directly):

{
  "mcpServers": {
    "chronary": {
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@chronary/mcp"],
      "env": {
        "CHRONARY_API_KEY": "chr_sk_..."
      }
    }
  }
}

Restart Claude Desktop after saving.

Cursor

Edit .cursor/mcp.json (project-level) or ~/.cursor/mcp.json (user-level):

macOS / Linux:

{
  "mcpServers": {
    "chronary": {
      "command": "npx",
      "args": ["-y", "@chronary/mcp"],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

Windows:

{
  "mcpServers": {
    "chronary": {
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@chronary/mcp"],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

VS Code Copilot

Edit .vscode/mcp.json (workspace) or run the MCP: Open User Configuration command for a user-level config. VS Code uses a different top-level key (servers) and requires an explicit type:

macOS / Linux:

{
  "servers": {
    "chronary": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@chronary/mcp"],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

Windows:

{
  "servers": {
    "chronary": {
      "type": "stdio",
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@chronary/mcp"],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

Claude Code

Edit .mcp.json at the project root, or ~/.claude.json for user-level:

macOS / Linux:

{
  "mcpServers": {
    "chronary": {
      "command": "npx",
      "args": ["-y", "@chronary/mcp"],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

Windows:

{
  "mcpServers": {
    "chronary": {
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@chronary/mcp"],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

Windsurf

Edit ~/.codeium/windsurf/mcp_config.json (%USERPROFILE%\.codeium\windsurf\mcp_config.json on Windows):

macOS / Linux:

{
  "mcpServers": {
    "chronary": {
      "command": "npx",
      "args": ["-y", "@chronary/mcp"],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

Windows:

{
  "mcpServers": {
    "chronary": {
      "command": "cmd",
      "args": ["/c", "npx", "-y", "@chronary/mcp"],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

Windsurf limit: Cascade enforces a hard cap of 100 total tools across all MCP servers and 20 tool calls per prompt. Chronary exposes 50; consider --tools filtering if you stack multiple servers.

Reducing context with --tools

Exposing all 50 tools uses LLM tokens on every request. For focused workflows, whitelist only what you need:

{
  "mcpServers": {
    "chronary": {
      "command": "npx",
      "args": [
        "-y", "@chronary/mcp",
        "--tools", "list_events,find_meeting_time,create_event"
      ],
      "env": { "CHRONARY_API_KEY": "chr_sk_..." }
    }
  }
}

Pointing at a non-production API

For self-hosted Chronary instances or development against a local API:

{
  "args": ["-y", "@chronary/mcp", "--base-url", "http://localhost:8787"]
}

Tools exposed

Tool annotations (readOnlyHint, destructiveHint, idempotentHint) are surfaced to MCP clients so hosts can decide whether to require user confirmation.

Troubleshooting

"spawn npx ENOENT" on Windows — use the cmd /c npx ... form shown above.

"CHRONARY_API_KEY is required" — the env block must be nested under the server entry, not at the top of the config file.

Tools aren't showing up — restart the MCP client after editing the config. Most clients only read the config on startup.

Verify the binary runs locally:

CHRONARY_API_KEY=test npx -y @chronary/mcp --help

Links

• Chronary docs
• MCP spec
• Report an issue

License

Apache-2.0