# Start verification ## Request POST to the following URL ``` POST https://loginwithlink.com/api/start_verification ``` Include: * The \`client\_secret\` you received in step 1 (lookup). * The \`email\` of the consumer. ## Response The response will confirm that an SMS has been sent, and will again show you redacted phone number to which it has been sent. (You can display this phone number to your user.) ### Notes * For now this is a separate step. * You might want to check if the user exists on Stripe just to update the button text from "Sign up" to "Log in". * Or, (to think about this), we could have this combined with the previous step. * In fact, that might be a good idea… so a merchant doesn't look up loads of emails without risking spamming all their users with surprise (and concerning) SMS codes. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.loginwithlink.com/use-api-only/lookup-email/start-verification.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.