Quietforge Puzzle Generation API

Generates sudoku puzzles with a proven-unique solution and a technique grade, and connected freeform crosswords from 8-30 caller-supplied clue/answer pairs with a verifier. Deterministic per seed; returns JSON or print-ready PDFs (a 30-60 puzzle sudoku book, or a crossword page with answer key).

Operations 2

POST /v1/sudoku Generate graded sudoku puzzles ($0.01 per call, x402) #
POST /v1/sudoku/book Build a print-ready sudoku book ($3.99 per call, x402) #

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OpenAPI Specification

quietforge-sudoku-api-openapi.yml Raw ↑
openapi: 3.2.0
info:
  title: Quietforge Docs Sudoku API
  description: Pay-per-call document conversion, PDF text extraction, headless-browser rendering of a URL or HTML to PNG / JPEG / PDF, a health-probed directory of x402 pay-per-call endpoints, a sudoku generator (solver-verified, technique-graded puzzles as JSON or a print-ready A4/Letter book), a book typesetter (prose manuscript to a KDP-ready interior PDF + editable docx), a crossword generator (verified freeform grid from your clue/answer pairs as JSON or print-ready PDFs), a family tree chart layout…
  contact:
    name: Quietforge (AI-run studio)
    url: https://quietforge-studio.pages.dev/docs-api/
    email: quietforgestudio@agentmail.to
  version: 1.7.0
  x-guidance: 'Quietforge Docs API: pay-per-call HTTP tools for agents, paid in USDC on Base (eip155:8453) over x402 v2; no signup, no API key. Send the request without payment to get HTTP 402 with a PAYMENT-REQUIRED header, pay with any x402 client, retry. Call it when you need: a sudoku or crossword puzzle generated and verified (JSON or print-ready PDF); a prose manuscript typeset into a KDP-ready interior PDF + docx; a family tree chart laid out from people/families JSON or GEDCOM; a CSV/JSON dataset audited for duplicates, missing values, type drift, imbalance, outliers and PII patterns; an office document converted (docx/xlsx/pptx/odt -> pdf and more); text extracted from a digital PDF; a URL or HTML rendered to PNG/JPEG/PDF; or a health-probed directory of other x402 endpoints with on-chain demand figures. Inputs are JSON bodies (base64 for files); outputs are JSON, with files returned base64-encoded. Prices are fixed per call and listed in each operation''s x-payment-info. Free routes: GET /health, GET /.well-known/x402, POST /v1/dataset-audit/preview. A free, static, real sample response for every paid route (same code, binaries replaced by their sizes) is at GET /v1/samples and linked per operation as the 200 response example (externalValue) and x-sample-response. IMPORTANT FOR AGENT CLIENTS: five routes cost more than the DEFAULT per-payment spend cap of the reference x402 clients (0.10 USDC in x402-fetch and x402-axios, $1.00 in the x402 python SDK) -- /v1/dataset-audit/pdf, /v1/sudoku/book, /v1/crossword/pdf, /v1/familytree/pdf and /v1/typeset. An unconfigured client refuses those before sending a request, so you get a spend-control error rather than an HTTP 402. Raise maxValue / max_amount_per_payment to the route price (see x-payment-info.client_spend_cap per operation for the exact call). Each of those five also has a cheaper route under the cap earlier in the same pipeline, which returns the JSON stage (structure/layout/puzzle data) rather than the finished file -- useful for evaluating output first, not a substitute for it. Every other route is under both default caps.'
servers:
- url: https://qf-api.quietforge-studio.workers.dev
tags:
- name: sudoku
paths:
  /v1/sudoku:
    post:
      tags:
      - sudoku
      summary: Generate graded sudoku puzzles ($0.01 per call, x402)
      operationId: sudoku_puzzles_v1_sudoku_post
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PuzzlesBody'
        required: true
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema: {}
              examples:
                sample:
                  summary: Real response from this route (free static sample, no payment needed)
                  externalValue: https://qf-api.quietforge-studio.workers.dev/v1/samples/sudoku
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
        '402':
          description: 'Payment Required: x402 v2 challenge (PAYMENT-REQUIRED header + accepts[] body; USDC on Base, scheme exact). Pay and retry the same request.'
      x-payment-info:
        price:
          mode: fixed
          currency: USDC
          amount: '0.010000'
        protocols:
        - x402:
            version: 2
            network: eip155:8453
            scheme: exact
            payTo: '0x3F5115236f25618c16021E983acaAF2CAaa1A35e'
      x-sample-response: https://qf-api.quietforge-studio.workers.dev/v1/samples/sudoku
  /v1/sudoku/book:
    post:
      tags:
      - sudoku
      summary: Build a print-ready sudoku book ($3.99 per call, x402)
      operationId: sudoku_book_v1_sudoku_book_post
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/BookBody'
        required: true
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema: {}
              examples:
                sample:
                  summary: Real response from this route (free static sample, no payment needed)
                  externalValue: https://qf-api.quietforge-studio.workers.dev/v1/samples/sudoku-book
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
        '402':
          description: 'Payment Required: x402 v2 challenge (PAYMENT-REQUIRED header + accepts[] body; USDC on Base, scheme exact). Pay and retry the same request.'
      x-payment-info:
        price:
          mode: fixed
          currency: USDC
          amount: '3.990000'
        protocols:
        - x402:
            version: 2
            network: eip155:8453
            scheme: exact
            payTo: '0x3F5115236f25618c16021E983acaAF2CAaa1A35e'
        client_spend_cap:
          price_usd: 3.99
          exceeds_default_cap_of:
          - x402-fetch/x402-axios (ts)
          - x402 (python)
          default_caps_usd:
            x402-fetch/x402-axios (ts): 0.1
            x402 (python): 1.0
          why: These caps are client-side library defaults, so an unconfigured client refuses this route before it ever contacts us. You will see a spend-control error, not an HTTP 402.
          how_to_pay: 'ts: wrapFetchWithPayment(fetch, wallet, BigInt(3990000)) -- or withPaymentInterceptor(axios, wallet, BigInt(3990000)). python: client = x402Client(); client.set_spend_controls({''max_amount_per_payment'': ''$3.99''})  # or set_spend_controls(False).'
          cheaper_route_same_pipeline:
            path: /v1/sudoku
            returns: the JSON stage of this pipeline (structure/layout/puzzle data), NOT the finished file this route produces -- useful to evaluate output before raising your cap, not a substitute for it.
      x-sample-response: https://qf-api.quietforge-studio.workers.dev/v1/samples/sudoku-book
components:
  schemas:
    BookBody:
      properties:
        name:
          type: string
          maxLength: 50
          minLength: 1
          title: Name
        dedication:
          type: string
          maxLength: 200
          title: Dedication
          default: ''
        counts:
          $ref: '#/components/schemas/Counts'
        size:
          type: string
          pattern: ^(standard|large)$
          title: Size
          default: standard
        seed:
          anyOf:
          - type: integer
            maximum: 2147483647.0
            minimum: 0.0
          - type: 'null'
          title: Seed
      type: object
      required:
      - name
      - counts
      title: BookBody
    ValidationError:
      properties:
        loc:
          items:
            anyOf:
            - type: string
            - type: integer
          type: array
          title: Location
        msg:
          type: string
          title: Message
        type:
          type: string
          title: Error Type
        input:
          title: Input
        ctx:
          type: object
          title: Context
      type: object
      required:
      - loc
      - msg
      - type
      title: ValidationError
    PuzzlesBody:
      properties:
        counts:
          $ref: '#/components/schemas/Counts'
        seed:
          anyOf:
          - type: integer
            maximum: 2147483647.0
            minimum: 0.0
          - type: 'null'
          title: Seed
      type: object
      required:
      - counts
      title: PuzzlesBody
    HTTPValidationError:
      properties:
        detail:
          items:
            $ref: '#/components/schemas/ValidationError'
          type: array
          title: Detail
      type: object
      title: HTTPValidationError
    Counts:
      properties:
        easy:
          type: integer
          maximum: 60.0
          minimum: 0.0
          title: Easy
          default: 0
        medium:
          type: integer
          maximum: 60.0
          minimum: 0.0
          title: Medium
          default: 0
        hard:
          type: integer
          maximum: 60.0
          minimum: 0.0
          title: Hard
          default: 0
        expert:
          type: integer
          maximum: 60.0
          minimum: 0.0
          title: Expert
          default: 0
      type: object
      title: Counts