MaSMT is a java based multi-agent system development framework, especially designed for development of English to Sinhala machine translation system. MaSMT also capable to develop any multi-agent based system through its architecture. The framework provides two types of agents, namely ordinary agents and manager agents. A manager agent consists of number of ordinary agents within its control. Further, manager agents can directly communicate with other manager agents and each and every ordinary agent in the swarm is assigned to a particular manager agent. An ordinary agent in a swarm can directly communicate only with the agents in its own swarm and its manager agent. The framework primarily implements object-object communication, XML based data passing and MySQL database connectivity to use agents’ ontology and message passing. Agent communication in the framework has been implemented to comply with FIFA-ACL specification.