ISBN Validate & Convert

Validates ISBN-10 and ISBN-13 check digits and converts between them when the 978 prefix allows it.

POST /v1/id/isbn · 1 credit · deterministic

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POST/v1/id/isbn

Request

{
  "isbn": "978-0-306-40615-7"
}

no request sent yet

Response

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Why this exists

Built for hostile input

A Turkish address arrives as "Cd." or "Cad." or "Caddesi", with the flat number glued to the building number. Generic parsers drop half of it silently. This one tells you what it could not place.

Every number carries its provenance

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Repeated inputs come from cache and cost zero credits. If a response ever fails its own schema, the call is refunded automatically.

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Validation1

/v1/id/isbn ISBN Validate & Convert deterministic 1 credit

Validates ISBN-10 and ISBN-13 check digits and converts between them when the 978 prefix allows it.

Catalogue and retail systems still mix ISBN-10 and ISBN-13. This checks the ISBN-10 weighted mod-11 digit (X allowed) and the ISBN-13 / EAN-13 alternating 1–3 check digit. When an ISBN-10 is valid it returns the ISBN-13 form (978 + body + new check). ISBN-13 values starting with 978 convert back to ISBN-10; 979 prefixes have no ISBN-10 equivalent and isbn10 stays null. Hyphens and spaces are stripped. A valid checksum is not proof the title exists in a national bibliography.

Parameters

isbn*

string

ISBN-10 or ISBN-13, with or without hyphens.

POST/v1/id/isbn

Request

{
  "isbn": "978-0-306-40615-7"
}

no request sent yet

Response

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Use it from an AI assistantthe same catalogue, exposed as MCP tools

Every endpoint is also published over the Model Context Protocol, so Claude, ChatGPT or your own agent can call it directly — no glue code, no wrapper functions. The assistant sees the same input schemas and the same metering.

Currently 37 tools. New endpoints appear automatically; nothing to update on your side.

claude_desktop_config.json

{
  "mcpServers": {
    "temsor": {
      "url": "https://api.temsor.com/mcp",
      "headers": { "x-api-key": "fk_live_…" }
    }
  }
}

Quickstart

Official client: npm install temsor-api · npmjs.com/package/temsor-api

Node.js

import Client from "temsor-api";

const api = new Client({ apiKey: KEY });
const r = await api.${(() => {
  const first = apis[0];
  return first.slug.split(/[/-]/).map((p, i) => (i === 0 ? p : p[0].toUpperCase() + p.slice(1))).join('');
})()}(${esc(JSON.stringify(apis[0].examples[0]?.input ?? {}))});
console.log(r, r.$meta);

cURL

curl -s https://api.temsor.com/v1/id/isbn \
  -H "content-type: application/json" \
  -H "x-api-key: fk_live_…" \
  -d '{"isbn":"978-0-306-40615-7"}'

JavaScript

const res = await fetch("https://api.temsor.com/v1/id/isbn", {
  method: "POST",
  headers: { "content-type": "application/json", "x-api-key": KEY },
  body: JSON.stringify({"isbn":"978-0-306-40615-7"})
});
const { data } = await res.json();

Python

import httpx
r = httpx.post("https://api.temsor.com/v1/id/isbn",
    headers={"x-api-key": KEY},
    json={"isbn":"978-0-306-40615-7"})
data = r.json()["data"]