Free API + MCP server · paid keys from $5/month

Number puzzles for your app, by API and MCP.

1,800 original Cage Grids (4×4 to 6×6, exactly one solution each), Target puzzles and Brick Pyramids at three levels, as JSON or printable SVG, with solutions and a daily puzzle. For puzzle apps, classroom tools, newsletters and AI agents. 50 free puzzles a day without a key.

Try it Get an API key

Live example: /v1/puzzle.svg?type=cage&level=easy&seed=demo

JSON

curl "https://sumbloom.cybermax-tools.workers.dev/v1/puzzle?type=cage&level=medium&seed=abc"
curl "https://sumbloom.cybermax-tools.workers.dev/v1/puzzle?type=target&daily=true"

Printable SVG

https://sumbloom.cybermax-tools.workers.dev/v1/puzzle.svg?type=pyramid&level=hard&solution=true

MCP (Claude, Cursor, any MCP client)

{"mcpServers":{"sumbloom-puzzles":{"url":"https://sumbloom.cybermax-tools.workers.dev/mcp"}}}

Get an API key

Original number puzzles for apps, classroom tools, newsletters and AI agents: 1,800 solver-checked Cage Grids (4x4 to 6x6, exactly one solution each), Target puzzles and Brick Pyramids at 3 levels, as JSON or printable SVG with solutions, plus a daily puzzle. Paid keys include commercial use in your app or product.

14-day money-back promise: if it doesn't work as described, email us within 14 days and we fix it or refund you in full. Refund terms.

Free

50 puzzles a day per IP · 30 per minute · no key, no sign-up

Try it now

Starter

$5/month

10,000 puzzles a month · 60 per minute

Get Starter key or $50/year, 2 months free

Pro recommended

$15/month

100,000 puzzles a month · 120 per minute

Get Pro key or $150/year, 2 months free

Pay with card, Apple Pay or Google Pay through Polar (merchant of record, sales tax/VAT handled). Your key appears right after checkout and in your email; manage or cancel any time in the customer portal. Send it as x-api-key: YOUR_KEY (or Authorization: Bearer YOUR_KEY, which MCP clients support). Check usage at /key. Failed calls are not counted. Puzzle APIs: API Ninjas needs its $39/month Developer plan for commercial use of its Sudoku API; SUDOKU All-Purpose PRO on RapidAPI is $49 for 50,000 (checked 27 Sep 2026). No rival generates cage, target and pyramid puzzles; Sumbloom Starter is $5/month for 10,000 and Pro $15 for 100,000, commercial use included.

With your key

curl -s "https://sumbloom.cybermax-tools.workers.dev/v1/puzzle?..." -H "x-api-key: YOUR_KEY"

# MCP (Claude Desktop, Cursor, VS Code)
{ "mcpServers": { "sumbloom": { "type": "http", "url": "https://sumbloom.cybermax-tools.workers.dev/mcp",
  "headers": { "Authorization": "Bearer YOUR_KEY" } } } }

# Usage so far
curl -s https://sumbloom.cybermax-tools.workers.dev/key -H "x-api-key: YOUR_KEY"

API reference

Tool: get_number_puzzle(type, level, seed?, daily?, include_solution?) · OpenAPI · llms.txt · pricing.json · Status

Example response

{
 "id": "cage-easy-89",
 "type": "cage",
 "name": "Cage Grid",
 "level": "easy",
 "seed": "demo",
 "rules": "Fill the NxN grid so every row and column holds 1..N once. The numbers in each cage must make its clue with the sign shown (- and / work in either order). A clue with no sign is that number.",
 "puzzle": {
  "size": 4,
  "cages": [
   {
    "cells": [
     [
      3,
      0
     ],
     [
      3,
      1
     ],
     [
      3,
      2
     ]
    ],
    "op": "+",
    "target": 8,
    "clue": "8+"
   },
   {
    "cells": [
     [
      0,
      0
     ],
     [
      0,
      1
     ]
    ],
    "op": "-",
    "target": 1,
    "clue": "1−"
   },
   {
    "cells": [
     [
      1,
      2
     ],
     [
      1,
      3
     ]
    ],
    "op": "/",
    "target": 2,
    "clue": "2÷"
   },
   {
    "cells": [
     [
      2,
      1
     ],
     [
      1,
      1
     ],
     [
      2,
      2
     ]
    ],
    "op": "*",
    "target": 12,
    "clue": "12×"
   },
   {
    "cells": [
     [
      1,
      0
     ],
     [
      2,
      0
     ]
    ],
    "op": "+",
    "target": 5,
    "clue": "5+"
   },
   {
    "cells": [
     [
      0,
      2
     ],
     [
      0,
      3
     ]
    ],
    "op": "+",
    "target": 7,
    "clue": "7+"
   },
   {
    "cells": [
     [
      2,
      3
     ],
     [
      3,
      3
     ]
    ],
    "op": "-",
    "target": 1,
    "clue": "1−"
   }
  ]
 },
 "svg": "https://sumbloom.cybermax-tools.workers.dev/v1/puzzle.svg?type=cage&level=easy&seed=demo",
 "more": {
  "book": "https://cybermax-tools-cybermax.static.hf.space/sumbloom-book/index.html",
  "buy": "https://data.cybermax-tools.workers.dev/buy/sumbloom-book?s=api-json",
  "note": "120 more puzzles like this, printable with answers: Sumbloom Puzzle Book ($5, classroom copies included)."
 }
}

Need them on paper? The Sumbloom Puzzle Book has 120 more puzzles (none from the API) with every answer, US Letter + A4, classroom copies included, for $5. Get the book