1. A computer-implemented method for converting authentication-tokens, comprising: receiving, at a computer, a command-execution request from a first application, wherein the command-execution request specifies a command to be executed by a second application and includes a first authentication-token that is created by the first application based on a user authenticating to the first application; verifying the first authentication-token at the computer; translating the first authentication-token to a form associated with the second application to produce a second authentication-token, wherein the second authentication-token is in a form different than the first authentication-token; modifying the command-execution request by replacing the first authentication-token with the second authentication-token to create a modified command-execution request; and sending the modified command-execution request to the second application, wherein the command-execution request includes a target Uniform Resource Locator (URL) which specifies a location of the second application, a second authentication-token type which specifies a form of the second authentication-token, a user identifier for a user who is associated with the first authentication-token, and payload data for the second application.