Daily puzzle API

Every Coronet daily is a plain JSON file at a stable URL: the same files the daily pages load. No key, no sign-up. Free for non-commercial use.

Endpoints

One file per game per day: <base URL><date>.json

Date format: YYYY-MM-DD, e.g. 2026-10-01. It's the calendar date of the daily, with no time zone: the site shows each player the board for their own local date. A date with no published board returns 404.

Example

curl https://playcoronet.com/games/tango/dailies/2026-10-01.json

{
  "id": "tango-daily-2026-10-01",
  "seed": "daily-2026-10-01",
  "difficulty": "medium",
  "givens": [0,2,0,2,0,1,0,0,0,1,0,0,0,0,0,0,2,0,1,2,0,0,0,0,0,0,0,0,0,1,0,1,0,0,2,0],
  "edges": [{"a":1,"b":2,"eq":false}, {"a":9,"b":15,"eq":true}, {"a":12,"b":13,"eq":true}, {"a":14,"b":15,"eq":false}, {"a":16,"b":22,"eq":true}],
  "solution": [2,2,1,2,1,1,2,1,2,1,1,2,1,1,2,1,2,2,1,2,1,2,2,1,2,2,1,2,1,1,1,1,2,1,2,2],
  "techniques": ["pairs","sandwich","balance","link"]
}

Response shape

Boards are flat arrays in row-major order: index row × size + column. Every game has:

• id, seed: stable identifiers for the board.
• difficulty: easy, medium or hard (Queens also has expert).
• techniques: the solving techniques the logic solver needed, easiest first.
• solution: the one solution. Keep it away from players until they've solved the board.

Plus, per game:

• Queens: size (5 to 12); regions, each cell's color region from 0 to size − 1; solution[row] is the column of that row's queen.
• Tango (6×6): givens, 0 empty, 1 sun, 2 moon; edges, the signs between neighboring cells a and b, with eq: true for = and false for ×.
• Sudoku and Mini Sudoku: variant (classic 9×9 or mini 6×6 with 3-wide, 2-tall boxes); givens, 0 for an empty cell; requires, the hardest technique the board is built around.

Caching and stability

• These are static files, not a live server: they're served with an ETag and open CORS (Access-Control-Allow-Origin: *), so you can fetch them from a browser and revalidate cheaply. One request per game per day is all you need.
• The URLs are stable. Fields may be added but won't be removed, so ignore any you don't recognize.
• Free for non-commercial use. For anything else, write to [email protected].