Abstract
In large language model (LLM)-driven multi-agent systems, disobey role specification (failure to adhere to the defined responsibilities and constraints of an assigned role, potentially leading to an agent behaving like another) is a major failure mode \cite{DBLP:journals/corr/abs-2503-13657}. To address this issue, in the present paper, we propose a quantitative role clarity to improve role consistency. Firstly, we construct a role assignment matrix S(\phi)=[s_{ij}(\phi)], where s_{ij}(\phi) is the semantic similarity between the i-th agent's behavior trajectory and the j-th agent's role description. Then we define role clarity matrix M(\phi) as \text{softmax}(S(\phi))-I, where \text{softmax}(S(\phi)) is a row-wise softmax of S(\phi) and I is the identity matrix. The Frobenius norm of M(\phi) quantifies the alignment between agents' role descriptions and their behaviors trajectory. Moreover, we employ the role clarity matrix as a regularizer during lightweight fine-tuning to improve role consistency, thereby improving end-to-end task performance. Experiments on the ChatDev multi-agent system show that our method substantially improves role consistency and task performance: with Qwen and Llama, the role overstepping rate decreases from 46.4\% to 8.4\% and from 43.4\% to 0.2\%, respectively, and the role clarity score increases from 0.5328 to 0.9097 and from 0.5007 to 0.8530, respectively, the task success rate increases from 0.6769 to 0.6909 and from 0.6174 to 0.6763, respectively.
