1. A method of dynamically propagating identity context information, the method comprising: receiving, by a first computer system, a request to invoke a web service; retrieving, by the first computer system, first security claims from application identity context information pertaining to a user; generating, by the first computer system, second security claims at runtime; packaging, by the first computer system, the first and second security claims into an authentication token; and transmitting, by the first computer system, the authentication token to a second computer system in a service request.