wassail

Advent of Code toolkit for Node.js.
A minimal CLI that fetches your puzzle input using an AOC_SESSION cookie.

Install

npm i -g wassail

Usage

# Export your Advent of Code session cookie
export AOC_SESSION=your_session_cookie

# Fetch today's input
wassail

# Fetch a specific year/day
wassail --year 2025 --day 1

Options

-y, --year   Year of the puzzle (defaults to current year)
-d, --day    Day of the puzzle (defaults to 1)
-h, --help   Show help

Requirements

• Node.js 18 or newer (uses built-in fetch)
• A valid AOC_SESSION cookie from adventofcode.com

How to get your session token

1. Log in to Advent of Code in your browser.
2. Open Developer Tools → Application/Storage → Cookies.
3. Copy the value of the cookie named session.
4. Set it in your environment:

   export AOC_SESSION=your_session_cookie

Notes

• Input is printed to stdout so you can redirect it:

  wassail --year 2025 --day 1 > input.txt

• Please cache your inputs locally and avoid excessive requests.
• MIT License

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