About QR Code Generator x402
QR Code Generator x402 is an API for turning text or URLs into configurable-size QR code PNGs returned as base64. It is intended for AI agents and other API clients, with pay-per-call access through x402 using USDC on Base and no API key.
Key features
- 01Generate QR codes from text or URLs
- 02Configurable QR size
- 03Base64 PNG output
- 04Pay-per-call x402 access
- 05USDC payments on Base
Use cases
- 01Create QR codes for shareable links
- 02Generate payment or Wi-Fi QR codes
- 03Encode vCard contact details
- 04Create event ticket barcodes
MCP support
The service exposes a QR-generation tool to MCP clients at https://qr-code.api.klymax402.com/mcp. The tool accepts text or a URL and returns base64 image data.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://qr-code.api.klymax402.com/mcpclaude mcp add --transport sse qr-code-x402 https://qr-code.api.klymax402.com/mcp{"mcpServers":{"qr-code-x402":{"type":"sse","url":"https://qr-code.api.klymax402.com/mcp"}}}Open in Cursor{"servers":{"qr-code-x402":{"type":"sse","url":"https://qr-code.api.klymax402.com/mcp"}}}Open in VS Code{"mcpServers":{"qr-code-x402":{"type":"sse","url":"https://qr-code.api.klymax402.com/mcp"}}}{"mcpServers":{"qr-code-x402":{"serverUrl":"https://qr-code.api.klymax402.com/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
Details
From the project READMEQR Code Generator API
Generate QR codes from text or URLs -- base64 PNG output, configurable size. Fast and lightweight. Pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.
Part of the klymax402 marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.
Quickstart -- MCP
Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):
{
"mcpServers": {
"qr-code": {
"url": "https://qr-code.api.klymax402.com/mcp"
}
}
}
Quickstart -- HTTP (x402)
curl -X POST "https://qr-code.api.klymax402.com/api/qr" \
-H "Content-Type: application/json" \
-d '{"data":"..."}'
# -> 402 Payment Required, with an x402 payment challenge in the response body
Any x402-aware client (@x402/fetch, x402-agent-tools, ATXP) handles the 402 -> sign -> retry cycle automatically.
Tools
| Tool | Method | Path | Price | Description |
|---|---|---|---|---|
utility_generate_qr_code | POST | /api/qr | $0.003 | Generate a QR code image from text or URL |
utility_generate_qr_code
Use this when you need to generate a QR code from text, a URL, or any string data. Returns base64 image data in JSON.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
data | string | yes | The text or URL to encode in the QR code |
size | number | no | QR code size in modules (default: 21 for version 1) |
Example response:
{"data":"https://example.com","image":"iVBORw0KGgo...","width":210,"height":210,"format":"png"}
When to use: generating shareable links, payment QR codes, Wi-Fi connection codes, vCard contact sharing, and event ticket barcodes.
Not for: screenshots (use capture_screenshot), PDFs (use document_generate_pdf).
Example agent prompts
- "Generate a QR code from text, a URL, or any string data"
Payment
- Protocol: x402 -- HTTP-native pay-per-call, no signup, no API key
- Network: Base L2 (
eip155:8453) - Asset: USDC
- Facilitator: Coinbase CDP (primary), PayAI (fallback)
- Also reachable via ATXP (OAuth-wrapped x402, RFC 9728 protected-resource metadata)
Part of klymax402
100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.
- Catalog: https://klymax402.com/llms.txt
- Full API reference: https://klymax402.com/llms-full.txt
- Live stats: https://klymax402.com/stats
License
MIT
Comments
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