Methods and apparatus authenticate a printed document associated with a source entity. The printed document includes a two-dimensional code (2-D code) that includes data encoded therein. The encoded data includes a resource locator to an intent. An image of the 2-D code is decoded to obtain the resource locator to an intent, and it is detected whether the resource locator to an intent includes a protocol identifier designating a secure 2-D code. If so, the protocol identifier is replaced with a protocol identifier used to access a secure server of the source entity located at a host portion of the resource locator. The secure server is accessed to obtain the intent. A certificate of the secure server is accessed and an electronic device displays an indicator of whether the certificate is valid and also displays the intent. The indicator may be used to decide whether the intent can be trusted.