AI summary of text or a web page API

AI summary of up to 8,000 characters of text, or of a public web page URL (main content fetched through SSRF-validated redirects and converted to Markdown, first 30,000 characters). Length short, medium or long; format paragraph, bullets or json. Returns summary, key points, detected language, source URL and title, input size and truncation flag. Generated by Anthropic Claude under a fixed Kit Rx prompt; AI-generated text may omit or misstate details.

$0.006 per call USDC over x402 v2 on Base, Polygon, Arbitrum, Avalanche or Sei. No signup, no API key. Requests that fail or match nothing are not charged.

Endpoint

GET https://api.kit-rx.com/v1/text/summarize

Parameters

Name	Type	Required	Description
`text`	string	no	Text to summarize, up to 8000 characters (URL-encoded). Give text or url, not both. e.g. `The city council voted 7-2 on Tuesday to approve a $48 million bond for road repairs...`
`url`	string	no	http or https URL of a public page to summarize instead of text. Default ports only; credentials, IP addresses, localhost and private or single-label names are rejected. e.g. `https://www.archives.gov/founding-docs/declaration-transcript`
`length`	string: short, medium, long	no	short (one or two sentences, up to 3 key points), medium (about 80-150 words, 3-5 key points, default) or long (about 250-400 words, 5-8 key points). e.g. `short`
`format`	string: bullets, paragraph, json	no	paragraph (prose, default), bullets (summary as a Markdown bullet list) or json (plain-text summary without Markdown; key_points as standalone factual sentences). e.g. `paragraph`

Example request

https://api.kit-rx.com/v1/text/summarize?url=https%3A%2F%2Fwww.archives.gov%2Ffounding-docs%2Fdeclaration-transcript&length=short

Without payment the server answers 402 Payment Required with the price (6000 atomic USDC) in the PAYMENT-REQUIRED header. Any x402 v2 client pays and retries automatically. A request with no parameters runs this example.

curl -i "https://api.kit-rx.com/v1/text/summarize?url=https%3A%2F%2Fwww.archives.gov%2Ffounding-docs%2Fdeclaration-transcript&length=short"

Pay from an agent

AgentCash: fetch the URL. OpenDexter MCP: x402_fetch. Kit Rx MCP server: https://api.kit-rx.com/mcp. Code:

import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { wrapFetchWithPayment } from "@x402/fetch";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.BUYER_KEY) });
const pay = wrapFetchWithPayment(fetch, client);
const res = await pay("https://api.kit-rx.com/v1/text/summarize?url=https%3A%2F%2Fwww.archives.gov%2Ffounding-docs%2Fdeclaration-transcript&length=short");
console.log(await res.json());

Example response

{
  "query": {
    "url": "https://www.archives.gov/founding-docs/declaration-transcript",
    "length": "short",
    "format": "paragraph"
  },
  "result": {
    "summary": "This page presents a transcription of the Declaration of Independence, adopted by the Continental Congress on July 4, 1776. It argues that people may dissolve political bonds with a government that becomes destructive of their rights, lists grievances against King George III, and declares the thirteen colonies free and independent states.",
    "key_points": [
      "Asserts that all men are created equal, endowed with unalienable rights including Life, Liberty and the pursuit of Happiness.",
      "Lists repeated abuses and usurpations by the King of Great Britain as justification for separation.",
      "Declares the United Colonies Free and Independent States, absolved from allegiance to the British Crown, and pledges mutual support with lives, fortunes and sacred honor."
    ],
    "language": {
      "code": "en",
      "name": "English"
    },
    "source": {
      "type": "url",
      "url": "https://www.archives.gov/founding-docs/declaration-transcript",
      "final_url": "https://www.archives.gov/founding-docs/declaration-transcript",
      "title": "Declaration of Independence: A Transcription | National Archives"
    },
    "chars_in": 9990,
    "truncated": false,
    "length": "short",
    "format": "paragraph",
    "model_family": "Claude",
    "ai_generated": true
  },
  "sources": [
    {
      "name": "Cloudflare DNS over HTTPS (JSON API)",
      "url": "https://developers.cloudflare.com/1.1.1.1/encryption/dns-over-https/make-api-requests/dns-json/"
    },
    {
      "name": "Cloudflare Workers AI toMarkdown",
      "url": "https://developers.cloudflare.com/workers-ai/features/markdown-conversion/"
    },
    {
      "name": "Anthropic Claude (AI-generated text)",
      "url": "https://www.anthropic.com/claude"
    },
    {
      "name": "Live HTTP(S) fetch of the URL",
      "url": "https://www.archives.gov/founding-docs/declaration-transcript"
    }
  ],
  "notes": [
    "AI-generated summary by Anthropic Claude under a fixed Kit Rx prompt; it can omit or misstate details, so important facts should be checked against the source.",
    "Page fetched live by the Kit Rx fetcher (User-Agent KitRx/1.0) and converted with Cloudflare Workers AI toMarkdown; content belongs to its publisher."
  ],
  "attribution": [
    "DNS resolved via Cloudflare 1.1.1.1 DNS-over-HTTPS."
  ],
  "generated_at": "2026-11-15T05:52:31.731Z"
}

Kit Rx: Pay-per-call data and safety tools for AI agents, paid in USDC over x402. No signup, no API key. Machine-readable: OpenAPI, llms.txt, /.well-known/x402, agent skills.