The Agent Toolkit provides a convenient API for sending DDE messages and parsing KQML and KIF. It is reimplemented for each language that will be used for the Agent Toolkit, so there is a CLIPS version, with a native CLIPS KQML parser, and a C++ version, with its own KQML and KIF parser. The Agent Toolkit API may therefore change slightly across implementations, but the functionality will be broadly similar, and any agent should be able to communicate with any other agent without compatibility problems.