<p> Traditional technology adoption models in agriculture fail to adequately capture the complex interplay of socio-technical factors that drive farmer decision-making, resulting in limited predictive accuracy and insufficient understanding of diffusion dynamics. Existing approaches predominantly rely on static econometric frameworks or simplified diffusion models that overlook the dynamic social interactions, trust networks, and heterogeneous decision-making processes that characterize real-world agricultural technology adoption. This gap hinders effective policy design and technology deployment strategies. To address these limitations, this paper presents AdoptAgriSim, a Socio-Technical Agent-Based Simulation Model for Predicting Smart Agriculture Adoption Dynamics, which integrates economic, social, and technological dimensions into a unified framework. The model employs multi-agent reinforcement learning and socio-economic network modelling to capture how individual farmers, peer networks, and market forces interact during the diffusion of technology. AdoptAgriSim incorporates a multi-objective decision mechanism that balances rational economic reasoning with social learning shaped by trust-based network structures. Using three real-world datasets from Iowa (USA), Europe, and India, the model achieves 94.2% prediction accuracy for five-year adoption intervals, outperforming existing diffusion and econometric models. It effectively reproduces emergent adoption behaviours such as technology clustering, peer-driven influence cascades, and region-specific diffusion trajectories. Significant contributions include^{<CitationRef CitationID="CR1">1</CitationRef>}: a socio-technical model integrating multi-dimensional decision factors^{<CitationRef CitationID="CR2">2</CitationRef>}; a reinforcement-based optimiser that accounts for both economic and non-economic objectives^{<CitationRef CitationID="CR3">3</CitationRef>}; dynamic network evolution mechanisms reflecting real-world social interactions; and^{<CitationRef CitationID="CR4">4</CitationRef>} extensive validation across diverse agricultural contexts. Results show that social factors contribute 34% more to adoption variance than previously estimated, underscoring the centrality of peer influence and trust networks in accelerating the diffusion of technology. The proposed framework offers valuable insights for policymakers and technology designers, highlighting that strengthening social connectivity and targeted network interventions can substantially accelerate sustainable agricultural transformation.</p>