qr-code

mcp-barcode

Make a QR code or a barcode in the conversation you are already in. Paste a URL and get a QR code you can put on a flyer. Give a client's invoice an EPC payment code their banking app scans and fills in for them. Print an EAN-13 for a product, a Code 128 for a shelf label, a WiFi code for the office wall, a vCard for a conference badge. Everything is drawn on your machine: no upload, no account, no API key, and no network call of any kind.

In the official MCP Registry (io.github.theluckystrike/barcode-qr-code-sepa-payment-ean13).

Listed on the AI Product Index - live remote endpoint at mcp.zovo.one/s/barcode, free tier, no signup.

npm publish for @theluckystrike/mcp-barcode is pending, so npx -y @theluckystrike/mcp-barcode returns 404 today. Until then, the .mcpb one-click bundle or a clone+build is the working path.

Install

Claude Desktop, ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "barcode": { "command": "npx", "args": ["-y", "@theluckystrike/mcp-barcode"] }
  }
}

Claude Code:

claude mcp add barcode -- npx -y @theluckystrike/mcp-barcode

Cursor, .cursor/mcp.json:

{
  "mcpServers": {
    "barcode": { "command": "npx", "args": ["-y", "@theluckystrike/mcp-barcode"] }
  }
}

Tools

tool	what it does
qr_create	Text or a URL as a QR code, at any error correction level, SVG or PNG
qr_wifi	A code that joins a WiFi network when scanned
qr_vcard	A code that adds a contact (vCard 3.0)
qr_payment_sepa	An EPC069-12 payment code a euro banking app scans: IBAN, name, amount, reference
invoice_payment_qr	The payment code for an invoice, using the IBAN and name from your shared business profile
barcode_create	Code 128, EAN-13, EAN-8 or UPC-A, with the check digit computed or verified
barcode_batch	Many codes in one call, into a directory (Pro)
code_list	What you have generated, and how much of this month's free allowance is left
license_status, license_activate	Free or Pro, and activating a key

Free vs Pro

	Free	Pro
Codes per calendar month	20	Unlimited
SVG (prints at any size)	Yes	Yes
PNG	No	Yes, 32 to 4000 px
barcode_batch	No	Yes, up to 500 rows a call
QR, WiFi, vCard, SEPA payment codes, all four barcode symbologies	Yes	Yes

Get Pro: https://mcp.zovo.one/buy/barcode - $19 one time, or $39 for every server in the suite, lifetime. Keys verify offline; nothing is sent anywhere.

A wrong check digit is refused, not redrawn

Give barcode_create twelve digits and the thirteenth is computed for you. Give it thirteen and the thirteenth is checked:

Error: EAN-13 check digit is wrong: "5901234123450" ends in 0, but the first 12 digits give 7.
Pass 5901234123457, or pass the first 12 digits and the check digit is computed. Nothing was written.

The alternative, silently redrawing the code the caller asked for, prints a label that scans as a different product, and nobody finds out until the till. The same rule applies to the IBAN in a payment code: it is validated with ISO 7064 mod 97 before anything is drawn, so a transposed pair of digits is caught here rather than by a payment that goes nowhere.

Measured: error correction M is free on a SEPA payment code, Q and H are not

A typical EPC payment record (IBAN, beneficiary, EUR 120.50, an invoice number) is 73 bytes. QR codes come in fixed capacity steps, so raising the error correction level does not raise the code size smoothly:

level	recoverable	QR version	modules a side	change
L	7%	4	33	baseline
M	15%	4	33	no change at all
Q	25%	6	41	+24%
H	30%	7	45	+36%

L and M land in the same version 4 symbol: at this payload size the extra recovery data still fits in the same box, so choosing L over M buys nothing and gives up half the damage tolerance. That is why M is the default here. Q and H are worth asking for only when the code will be printed small, on something that creases, or behind a logo. On a 300 px PNG the same step costs bytes too: 2,419 at M against 3,462 at H.

Measured: SVG is flat, PNG grows 14x, and they cross at about 200 px

The same payment code written both ways, at five sizes:

requested size	PNG bytes	SVG bytes
128 px	1,481	2,079
256 px	2,186	2,079
512 px	3,589	2,079
1024 px	7,585	2,081
2048 px	21,688	2,081

An SVG carries the module grid, not the pixels, so its size barely moves: the two extra bytes at 1024 px are the width attribute getting longer. Below roughly 200 px a PNG is smaller; above it the PNG grows without limit and the SVG does not, and the SVG is the one that stays sharp when a printer scales it up. That is the reason the free tier is the SVG tier rather than a small-PNG tier: for the thing most people do with a code, put it in a document and print it, SVG is the better file, not the consolation prize.

Privacy

Everything stays on your machine. There is no network code in this server at all: no fetch, no HTTP client, no telemetry. Codes are written where you say, and a small register of what was generated lives under ~/.local/share/mcp-servers/barcode/ (or $XDG_DATA_HOME). License keys verify offline with a public key.

Built by theluckystrike. Support: [email protected]

Use these docs as an MCP server

Any MCP client (Claude, Cursor, Windsurf, VS Code) can read this repository's documentation directly via GitMCP - no install:

• Docs MCP URL: https://gitmcp.io/theluckystrike/mcp-barcode