cal2prompt

What is cal2prompt?

cal2prompt is a command-line tool that fetches your schedule (e.g., from Google Calendar) and converts it into a custom prompt or text snippet via a Jinja2 template engine. It can output directly to stdout, or run as an experimental MCP (Model Context Protocol) server.

How to use cal2prompt?

Install via brew install shuntaka9576/tap/cal2prompt or build from source with Cargo. Set up a Google OAuth2 client, create Lua configuration files (~/.config/cal2prompt/config.lua and secrets.lua), then run cal2prompt with date‑range flags (e.g., --today, --this-week) or use the mcp subcommand to launch the experimental MCP server.

Key features of cal2prompt

• Google Calendar integration via Calendar API v3
• Custom LLM prompt generation with a Jinja2 template engine
• High‑speed processing built with the Rust ecosystem
• Experimental MCP (Model Context Protocol) server mode

Use cases of cal2prompt

• Generate a daily or weekly schedule summary as a prompt for an AI assistant
• Feed live calendar events into an LLM via the MCP server (e.g., Claude Desktop)
• Produce custom‑formatted text snippets for time‑blocking or status reports
• Combine multiple Google Calendars into a single chronological overview

FAQ from cal2prompt

How does authentication work?

cal2prompt uses Google OAuth2. You must create your own Google project and OAuth client; the generated token is stored in ~/.local/share/cal2prompt/oauth. The first run automatically starts the authentication flow.

What configuration format does cal2prompt use?

Configuration is written in Lua using two files: secrets.lua for sensitive data (client ID, client secret, calendar IDs) and config.lua for the main setup (time zone, template, etc.).

How can I use cal2prompt as an MCP server with Claude Desktop?

Add a mcpServers entry in claude_desktop_config.json specifying the full path to the cal2prompt binary and the mcp argument, plus the HOME environment variable.

Are there any known limitations?

The MCP mode is experimental and may change without notice. You must supply your own Google Calendar API token; the project owner cannot provide a pre‑approved client due to security and approval constraints.

Where are OAuth tokens stored?

Tokens are stored in the file defined by the settings.oauthFilePath configuration option, defaulting to ~/.local/share/cal2prompt/oauth.