Hi, I'm Matteo!
I'm a Research Engineer at kapa.ai (YC S23).
Before that, I completed my PhD in the Collaborative AI group at the University of Stuttgart, advised by Prof. Andreas Bulling, with a focus on theory of mind in AI.
During my PhD, I spent some time as a Visiting Graduate Scholar at the SCAI Lab, Johns Hopkins University, advised by Prof. Tianmin Shu.
I hold a BSc and a MSc in Physics from the University of Padua.
[LinkedIn] [Google Scholar] [GitHub]
I am currently working on RAG and search agents. In particular, I'm interested in multimodal RAG, agent training, and planning.
My PhD focused on how AI can understand others' mental states such as beliefs, goals, preferences, and intentions — a concept known as theory of mind — and how this understanding can improve human–AI interaction. In particular, my work covers:
The Yokai Learning Environment: Tracking Beliefs Over Space and Time
C Ruhdorfer, M Bortoletto, J Forkel, J Foerster, A Bulling
RLC 2026
[ArXiv] [Code]
Unsupervised Partner Design Enables Robust Ad-hoc Teamwork
C Ruhdorfer, M Bortoletto, V Oei, A Penzkofer, A Bulling
ICML 2026 (oral, top 0.7%)
[ArXiv] [Code]
ProToM: Promoting Prosocial Behaviour via Theory of Mind-Informed Feedback
M Bortoletto, Y Zhou, L Ying, T Shu, A Bulling
ACL 2026 Findings
[ArXiv] [Website] [Code]
ToM-SSI: Evaluating Theory of Mind in Situated Social Interactions
M Bortoletto, C Ruhdorfer, A Bulling
EMNLP 2025
[ArXiv] [Proceedings] [Code] [Poster]
Brittle Minds, Fixable Activations: Understanding Belief Representations in Language Models
M Bortoletto, C Ruhdorfer, L Shi, A Bulling
EMNLP 2025 Findings
[ArXiv] [Proceedings] [Code] [Poster] [ICML 2024 Workshop on Mechanistic Interpretability]
The Overcooked Generalisation Challenge
C Ruhdorfer, M Bortoletto, A Penzkofer, A Bulling
TMLR
[ArXiv] [Openreview] [Code]
Explicit Modelling of Theory of Mind for Belief Prediction in Nonverbal Social Interactions
M Bortoletto, C Ruhdorfer, L Shi, A Bulling
ECAI 2024 (oral)
[ArXiv] [Code]
Limits of Theory of Mind Modelling in Dialogue-Based Collaborative Plan Acquisition
M Bortoletto, C Ruhdorfer, A Abdessaied, L Shi, A Bulling
ACL 2024
[ArXiv] [Proceedings] [Code] [Poster]
Neural Reasoning about Agents' Goals, Preferences, and Actions
M Bortoletto, L Shi, A Bulling
AAAI 2024
[ArXiv] [Code] [Poster]
Improving Neural Saliency Prediction with a Cognitive Model of Human Visual Attention
E Sood, L Shi, M Bortoletto, Y Wang, P Müller, A Bulling
CogSci 2023
[Proceedings]
University: matteo [dot] bortoletto [at] uni-stuttgart [dot] de
Personal: mabo22 [dot] lab [at] gmail [dot] com