Word Ladder Generator API Reference

Overview

Returns the puzzle, solution path, and step count. Includes printable HTML with empty rungs for solving.

Endpoint

One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.

GEThttps://api.apiverve.com/v1/wordladder

curl "https://api.apiverve.com/v1/wordladder?start=cold&end=warm&difficulty=medium&count=1&image=true" \
  -H "x-api-key: your_api_key_here"

const res = await fetch('https://api.apiverve.com/v1/wordladder?start=cold&end=warm&difficulty=medium&count=1&image=true', {
  headers: { 'x-api-key': 'your_api_key_here' },
});

if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);

const { data } = await res.json();
console.log(data);

import requests

res = requests.get(
    "https://api.apiverve.com/v1/wordladder?start=cold&end=warm&difficulty=medium&count=1&image=true",
    headers={"x-api-key": "your_api_key_here"},
    timeout=15,
)
res.raise_for_status()

print(res.json()["data"])

package main

import (
	"fmt"
	"io"
	"net/http"
)

func main() {
	req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/wordladder?start=cold&end=warm&difficulty=medium&count=1&image=true", nil)
	req.Header.Set("x-api-key", "your_api_key_here")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	out, _ := io.ReadAll(res.Body)
	fmt.Println(string(out))
}

Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.

Authentication

Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.

401 is the only auth verdict

A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.

Parameters

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.

Parameter	Type	Description
`start`Optional	string	Starting word (3-6 letters) length 3–6
`end`Optional	string	Ending word (same length as start) length 3–6
`difficulty`Optional	string	Difficulty level `easymediumhard` default medium
`count`Optional	integer	Number of puzzles default 1 · range 1–5
`image`OptionalPremium	boolean	Set to true to generate a downloadable puzzle image

Response

Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.

Sample response

{
  "status": "ok",
  "error": null,
  "data": {
    "puzzles": [
      {
        "startWord": "ANIL",
        "endWord": "CUED",
        "steps": 5,
        "solution": [
          "ANIL",
          "ARIL",
          "ARID",
          "IRID",
          "IRED",
          "CRED",
          "CUED"
        ],
        "solvable": true,
        "difficulty": "medium"
      }
    ],
    "count": 1,
    "difficulty": "medium",
    "html": "<html><head><title>Word Ladder</title><style>body {font-family: Arial, sans-serif; padding: 20px; max-width: 600px; margin: 0 auto;}h1 {text-align: center; color: #4CAF50;}.puzzle {background: #f5f5f5; padding: 25px; margin: 20px 0; border-radius: 10px;}.words {display: flex; justify-content: space-between; align-items: center; margin: 20px 0;}.word {font-size: 28px; font-weight: bold; letter-spacing: 3px; padding: 15px 25px; border-radius: 10px;}.start {background: #4CAF50; color: white;}.end {background: #2196F3; color: white;}.arrow {font-size: 30px; color: #999;}.steps {text-align: center; font-size: 14px; color: #666; margin-bottom: 15px;}.ladder {display: flex; flex-direction: column; align-items: center; gap: 10px; margin: 20px 0;}.rung {width: 150px; height: 40px; border: 2px dashed #ccc; border-radius: 5px; display: flex; align-items: center; justify-content: center; font-size: 18px; letter-spacing: 5px;}.hint {font-size: 13px; color: #888; font-style: italic; margin-top: 10px;}</style></head><body><h1>Word Ladder</h1><p style='text-align:center;'>Change one letter at a time to get from the first word to the last</p><div class='puzzle'><div class='steps'>Puzzle #1 - 5 steps</div><div class='words'><span class='word start'>ANIL</span><span class='arrow'>→</span><span class='word end'>CUED</span></div><div class='ladder'><div class='rung'>_ _ _ _</div><div class='rung'>_ _ _ _</div><div class='rung'>_ _ _ _</div><div class='rung'>_ _ _ _</div><div class='rung'>_ _ _ _</div></div></div></body></html>",
    "image": {
      "imageName": "6f0f9e5e-ce0d-4570-a706-8fc5ccbfc948_wordladder.png",
      "format": ".png",
      "downloadURL": "https://storage.googleapis.com/apiverve/APIData/wordladder/6f0f9e5e-ce0d-4570-a706-8fc5ccbfc948_wordladder.png?GoogleAccessId=635500398038-compute%40developer.gserviceaccount.com&Expires=1766010731&Signature=FQwH%2FqXC0eYHgHqGKfBoEETrcXALoIpkf2z7HCkmYcFu2IgL2uMbCBi22tEsrlY3yOkksRuZ56C2685lLi98CWvgCF1J9UrYaAWjFtLesnHZ0i%2B0SWYIy5wZLWnVq4UrJDLZVrvSe8lh21mQJrduVY8QqV%2FI0sViUlnlndLMFUfhEQedKYAGRtmXjJlpl1YA9A9%2BtJoqRvMm4YStfJyLJmExPQKnPiRoP6EB6%2B8%2F1WUq5vH3%2BWglijVroxaJ%2BJy6kgQ8qTuVX9%2FzFi8R0DDHZtd0IpcTL8EBvNvHnjRPS4lZB%2Bm3k9GCxqGCnsj8pssu6ymtzGNEqA%2BBqAthODekWw%3D%3D",
      "expires": 1766010731681
    }
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Field	Type	Example	Description
`puzzles`	array[1]		Array of word ladder puzzle objects with solutions
`startWord`	string	`"ANIL"`	Starting word for the puzzle transformation
`endWord`	string	`"CUED"`	Target word to transform the starting word into
`steps`	number	`5`	Number of letter-changing steps required to solve
`solution`Premium	array	`[ANIL, ...]`	Complete sequence of valid words forming solution path
`solvable`	boolean	`true`	Whether the puzzle has a valid solution path
`difficulty`	string	`"medium"`	Difficulty level of the puzzle (easy, medium, hard)
`count`	number	`1`	Total number of puzzles generated in response
`difficulty`	string	`"medium"`	Overall difficulty level of generated puzzles
`html`Premium	string	"<html><head><title>Word Ladder</title><style>body {font-family: Arial, sans-serif; padding: 20px; max-width: 600px; margin: 0 auto;}h1 {text-align: center; color: #4CAF50;}.puzzle {background: #f5f5f5; padding: 25px; margin: 20px 0; border-radius: 10px;}.words {display: flex; justify-content: space-between; align-items: center; margin: 20px 0;}.word {font-size: 28px; font-weight: bold; letter-spacing: 3px; padding: 15px 25px; border-radius: 10px;}.start {background: #4CAF50; color: white;}.end {background: #2196F3; color: white;}.arrow {font-size: 30px; color: #999;}.steps {text-align: center; font-size: 14px; color: #666; margin-bottom: 15px;}.ladder {display: flex; flex-direction: column; align-items: center; gap: 10px; margin: 20px 0;}.rung {width: 150px; height: 40px; border: 2px dashed #ccc; border-radius: 5px; display: flex; align-items: center; justify-content: center; font-size: 18px; letter-spacing: 5px;}.hint {font-size: 13px; color: #888; font-style: italic; margin-top: 10px;}</style></head><body><h1>Word Ladder</h1><p style='text-align:center;'>Change one letter at a time to get from the first word to the last</p><div class='puzzle'><div class='steps'>Puzzle #1 - 5 steps</div><div class='words'><span class='word start'>ANIL</span><span class='arrow'>→</span><span class='word end'>CUED</span></div><div class='ladder'><div class='rung'>_ _ _ _</div><div class='rung'>_ _ _ _</div><div class='rung'>_ _ _ _</div><div class='rung'>_ _ _ _</div><div class='rung'>_ _ _ _</div></div></div></body></html>"	Printable HTML puzzle template with empty rungs
`image`	object	`{...}`
`imageName`Premium	string	`"6f0f9e5e-ce0d-4570-a706-8fc5ccbfc948_wordladder.png"`	Unique filename for the generated puzzle image
`format`Premium	string	`".png"`	Image file format extension (e.g., .png)
`downloadURL`Premium	string	"https://storage.googleapis.com/apiverve/APIData/wordladder/6f0f9e5e-ce0d-4570-a706-8fc5ccbfc948_wordladder.png?GoogleAccessId=635500398038-compute%40developer.gserviceaccount.com&Expires=1766010731&Signature=FQwH%2FqXC0eYHgHqGKfBoEETrcXALoIpkf2z7HCkmYcFu2IgL2uMbCBi22tEsrlY3yOkksRuZ56C2685lLi98CWvgCF1J9UrYaAWjFtLesnHZ0i%2B0SWYIy5wZLWnVq4UrJDLZVrvSe8lh21mQJrduVY8QqV%2FI0sViUlnlndLMFUfhEQedKYAGRtmXjJlpl1YA9A9%2BtJoqRvMm4YStfJyLJmExPQKnPiRoP6EB6%2B8%2F1WUq5vH3%2BWglijVroxaJ%2BJy6kgQ8qTuVX9%2FzFi8R0DDHZtd0IpcTL8EBvNvHnjRPS4lZB%2Bm3k9GCxqGCnsj8pssu6ymtzGNEqA%2BBqAthODekWw%3D%3D"	Cloud storage URL to download the puzzle image
`expires`Premium	number	`1766010731681`	Unix timestamp when download URL expires

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.

Status	Meaning	What to do
`400`	Input was rejected	Read `error`; it names the parameter.
`401`	Key missing or invalid	Check the header name and the key value.
`403`	Key valid, but not permitted	A key restriction or IP allow-list; see key scoping.
`429`	Rate limited, or out of credits	Read `error` to tell them apart; see rate limits.

Use cases

Word Games: Create word ladder challenges for puzzle apps
Education: Teach vocabulary and word relationships
Brain Training: Develop problem-solving and word skills
Competitions: Generate puzzles for word game tournaments

Other ways to use Word Ladder Generator

Set up Word Ladder Generator on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.

Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.VerveKit →Reference →

Word Ladder Generator