Constrasting the standard framework based on agent-to-agent direct communication, in this paper we focus on agent interaction with the environment.
In particular, the environment is seen as populated by coordination artifacts, automatising coordination tasks and mediating agent interaction.
As a semantic framework for this context we propose operating instructions, which the agent reads and interprets to become aware of the allowed actions and perceptions at a given time, and the MAS infrastructure can exploit to enforce correct agent behaviours and detect wrong ones.
This allows us to conceptually handle a number of crucial aspects related to agent interaction, including interaction protocols, timing properties — such as delays and timeouts —, and a notion of contract featuring violation and guarantees.

Formally, our framework is based on a process algebra featuring <i></i> explicit connection between action and its related perceptions, <i>(ii)</i> a time-based branch operator, <i>(iii)</i> violation and guarantee deadlock states, and <i>(iv)</i> association of mental properties to interactions.