Keyword extraction

Top keywords and two-word phrases by frequency (stopwords removed). Cheap, deterministic signal for routing, tagging, and dedup.

Input

Field	Type	Description
text *	string	Text to analyze (max 500KB)
limit	number	Max keywords (default 15)

Example output

{
  "keywords": [
    {
      "term": "payment",
      "count": 9
    }
  ],
  "phrases": [
    {
      "term": "x402 protocol",
      "count": 4
    }
  ]
}

Try it — see the 402 challenge (free)

curl -i -X POST https://agent402.tools/api/keywords \
  -H "Content-Type: application/json" \
  -d '{"text":"Long article text…","limit":10}'

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

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

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/keywords", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "text": "Long article text…",
    "limit": 10
  }),
});

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