The tokens are bound to a specific project and will only allow operating on elements within the project scope. You are required to supply the token with every request in order to gain access to your data, otherwise, the call will fail and an appropriate error message will be shown.
Generating New Token
The token management page is available in the settings section of your project inside API Token subcategory ( Project > Settings > API Token ). You can generate multiple tokens each with a different name and HTTP method access. To generate new token simply provide a friendly name and select required HTTP methods, a confirmation pop-up will show and a token will be generated in the table below. To copy your token click on the copy button on the right or triple click on the token itself to select it.