About Check Digit Validator
Validates IBAN/ISBN/EAN/Luhn checksums and finds the one wrong digit
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
Endpoint
https://check-digit.gumballtools.com/api/mcpCopy install command
Claude CodeTerminal
claude mcp add --transport http com-gumballtools-check-digit https://check-digit.gumballtools.com/api/mcpCursor.cursor/mcp.json
{"mcpServers":{"com-gumballtools-check-digit":{"type":"http","url":"https://check-digit.gumballtools.com/api/mcp"}}}Open in CursorVS Code.vscode/mcp.json
{"servers":{"com-gumballtools-check-digit":{"type":"http","url":"https://check-digit.gumballtools.com/api/mcp"}}}Open in VS CodeClaude Desktopclaude_desktop_config.json
{"mcpServers":{"com-gumballtools-check-digit":{"type":"http","url":"https://check-digit.gumballtools.com/api/mcp"}}}Windsurf~/.codeium/windsurf/mcp_config.json
{"mcpServers":{"com-gumballtools-check-digit":{"serverUrl":"https://check-digit.gumballtools.com/api/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
1| Parameter | Type | Required | Description |
|---|---|---|---|
| input | string | Yes | The number to check, e.g. "DE89370400440532013000". Spaces and hyphens are stripped automatically; anything else must match the declared format exactly. |
| format | enum | Yes | Which checksum to apply — one of: iban, isbn10, isbn13, ean13, upca, luhn. Required; a bare number is not auto-detected because the same digits can be validly checked under more than one format with different results.iban | isbn10 | isbn13 | ean13 | upca | luhn |
Details
The maintainer has not added details yet. Check the README in the repository.
Comments
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