In a heterogeneous world, concurrent distributed development has led to many types of multi-agent systems that offer diverse functionality in agents as different types of platforms are not in a position to interoperate. Agents from different platforms are likely to use different types of messages or message formats and the interpretation is likely to differ. The main driver for interoperability is partly the customer who strives for universality when accessing multiple services, and partly producers who often need to act in fast to obtain a sustainable customer base. Implementations of agent systems differ greatly in architecture thereby negatively affecting interoperability, system diversity, rapid proliferation of agent technology, and advancement of the industry. In order to standardize some aspects of agent technology, considerable research has been conducted in the area of interoperability of agent technologies. Hence, it would be interesting to find out what agent systems interoperability frameworks have been proposed in the last few years. It would also be interesting to find out what interoperability assessment models exist. To address these issues, this paper presents the findings of a comprehensive literature review conducted with the aim of establishing existing agent based interoperability frameworks and interoperability assessment models.