# Why does MessageBird need my mobile phone number? We ask for your mobile number in order to send you a verification code and to register your mobile in your account for free test credits! During your testing phase, you are given 10 free SMS to send messages to yourself, so to whitelist the number that you are going to send to, we verify it in your account when you sign up, this is only 'stored' for your trial period. --- # 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.bird.com/connectivity-platform/accounts-workspaces-users-subaccounts/why-does-messagebird-need-my-mobile-phone-number.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.