Other · Remote MCP server
Check Digit Validator
Validates IBAN/ISBN/EAN/Luhn checksums and finds the one wrong digit.
What the MCP Registry states
The entry as published to the official MCP Registry (read 2026-10-04), latest version.
- Registry name
com.gumballtools/check-digit- Version
- 0.1.0
- Status
- Active
- Category
- other
- Transport
- Streamable HTTP
- Published
- 2026-09-05
- Updated
- 2026-09-05
- Publisher
- com.gumballtools · 14 servers with pages here
- Website
- check-digit.gumballtools.com
- Repository
- github.com/bwalvoord/gumball
- Source
- Registry API entry
Remote endpoints
| Transport | URL | Headers declared |
|---|---|---|
| Streamable HTTP | https://check-digit.gumballtools.com/api/mcp | None |
How to connect Check Digit Validator
Check Digit Validator is a remote MCP server: there is nothing to install. Its endpoint is https://check-digit.gumballtools.com/api/mcp, served over Streamable HTTP. In an assistant that accepts remote MCP servers (often under a setting named connectors, integrations or tools), add a new server and give it this URL; in a client configured by file, add it as a remote (HTTP) server with the same URL.
No headers are declared in the registry entry. If the server needs you to sign in, a client that supports MCP authorization opens the service's own sign-in page when it first connects.
Derived from the registry entry, not tested here. What the server does, and on what terms, is set by its publisher; check its repository or website before giving it access to your accounts or files. How to add an MCP server to an assistant · Before you connect
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