Add text watermark

Stamp customizable text — CONFIDENTIAL, DRAFT, a name — across the pages of a PDF.

At a glance

MCP tool	add_text_watermark
HTTP endpoint	POST /v1/watermark/text
Price	$0.05
Input	One PDF + watermark text
Output	The PDF with the text watermark applied to every page

Parameters

Parameter	Type	Required	Description
file	file	yes	Source PDF.
text	string	yes	The watermark text, e.g. CONFIDENTIAL.
template	string	no	A preset that controls style and layout (e.g. diagonal, footer). Defaults to a centered diagonal stamp.
position	string	no	Placement override, e.g. center, top, bottom, diagonal.
opacity	number	no	0–1. Default 0.3.
rotation	number	no	Degrees to rotate the text.

MCP example

Add a “CONFIDENTIAL” watermark across every page of https://example.com/merged.pdf.

{
  "file": "https://example.com/merged.pdf",
  "text": "CONFIDENTIAL",
  "position": "diagonal",
  "opacity": 0.3
}

HTTP example

curl

curl -i -X POST https://api.pdfasyougo.com/v1/watermark/text \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <base64-encoded-payment-payload>" \
  -d '{"file":"https://example.com/merged.pdf","text":"CONFIDENTIAL","position":"diagonal","opacity":0.3}'

TypeScript

import { wrapFetchWithPayment } from 'x402-fetch';
import { privateKeyToAccount } from 'viem/accounts';

const account = privateKeyToAccount(process.env.X402_WALLET_PRIVATE_KEY as `0x${string}`);
const fetchWithPay = wrapFetchWithPayment(fetch, account);

const res = await fetchWithPay('https://api.pdfasyougo.com/v1/watermark/text', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    file: 'https://example.com/merged.pdf',
    text: 'CONFIDENTIAL',
    position: 'diagonal',
    opacity: 0.3,
  }),
});
console.log((await res.json()).output.url);

Response

{
  "output": {
    "url": "https://files.pdfasyougo.com/o/c4a1…?token=…",
    "expires_at": "2026-06-29T12:00:00Z",
    "pages": 24,
    "bytes": 191000
  },
  "operation": "watermark.text",
  "cost": "0.05 USDC"
}

Notes

• The watermark is applied to every page.
• template chooses a built-in style; position, opacity, and rotation fine-tune it.
• To overlay a logo or image instead of text, use Add image watermark.

Note

Watermarking overlays content on top of the existing pages; it doesn’t flatten or rasterize the original text.