We present NatSTV, a tool for approximate verification of natural strategic ability in multi-agent systems. The tool builds on our model checker STV (STrategic Verifier), and implements heuristic synthesis of natural strategies for asynchronous agents with imperfect information and recall. All of that is available through a web interface, with no need to install or configure the software by the user.

In this paper, we present a substantially enhanced version of our software tool STV (STrategic Verifier), dedicated to strategy synthesis and model checking of strategic abilities in multi-agent systems. The new extension, called STV+FLY, incorporates an advanced strategy synthesis algorithm that enables model checking with on-the-fly generation of the global model. This innovative approach allows for the verification of some strategic properties without generating the entire global state space, thus avoiding an important bottleneck and significantly improving the efficiency.