CheckDigit

dev.workers.mike-tusa.checkdigitPublished by checkdigit.mike-tusa.workers.devOfficial publisherv0.2.1Updated Oct 28, 2026

Offline check-digit validation for IBAN, BIC, EU VAT, GTIN/EAN/UPC and ISBN. Format check only.

VerifiedStreamable HTTPWeb executableFinanceDeveloper Tools

Overview

AI-generated overview

Remote MCP server that validates the format and check digits of IBAN, BIC, EU VAT, GTIN/EAN/UPC and ISBN identifiers.

What you can do
  • Validate one identifier's format and check digits, with automatic type detection or an explicit type
  • Cover IBAN (per-country length and layout), BIC/SWIFT, EU VAT checksums, GTIN/EAN-8, UPC-A, EAN-13, GTIN-14 and ISBN-10/13
  • Read service metadata: version and build, supported IBAN and VAT countries, GTIN formats, disclaimer and current limits
When to use it
Useful when an assistant needs to sanity-check bank, tax or product identifiers it encounters or generates, for example while cleaning data or reviewing forms, without calling a full validation service.
Requirements
A remote streamable HTTP endpoint; no local package or runtime. An optional Authorization header with a bearer key raises rate limits, but the service works without one.
Before you install
Validation is format and check-digit only, so a passing result does not prove an account, business or product exists; EU VAT numbers are checked offline and VIES is not queried. The optional Authorization header carries a secret key, and identifiers submitted are sent to a third-party hosted service.

Installation

In SourceWeft

  1. Open CheckDigit in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/dev.workers.mike-tusa.checkdigit%2Fcheckdigit/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "checkdigit": {
      "type": "http",
      "url": "https://checkdigit.mike-tusa.workers.dev/mcp"
    }
  }
}

Tools

2

validate_code

Validate an IBAN, BIC, EU VAT number, GTIN/EAN/UPC or ISBN

Check the format and check digits of one identifier: IBAN (ISO 13616, per-country length and layout), BIC/SWIFT (ISO 9362 format and country), EU VAT number (offline checksum, VIES not queried), GTIN/EAN-8/UPC-A/EAN-13/GTIN-14 (GS1 mod 10) or ISBN-10/13. type "auto" (default) detects the type from the shape. Returns valid, a reason when invalid (e.g. the expected check digit), and normalized/formatted forms. Format check, not a compliance check: valid does not mean the account, registration or product exists. The code is sent in a POST body and not stored or logged. Read-only. Same engine, keys and limits as POST /v1/{type}.

Parameterscoderequiredtype

get_meta

Service version, supported formats and limits

Return the service version and build, supported IBAN and VAT countries, GTIN formats, the disclaimer and the current limits. Does not count as a check. Read-only. Same data as GET /v1/meta.

Takes no parameters.

Version history

1
  1. v0.2.1LatestOct 15, 2026

Score

72% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts

    Publish an icon in the registry entry.

  • Documentation15 pts

    Declare a GitHub repository with a README, or serve resource_documentation in the OAuth protected-resource metadata.

  • LicenseNot applicable

    A hosted service is used under its provider's terms, so no license is expected here. This check is left out of the percentage.