As artificial intelligence (AI) becomes increasingly integrated across industries, its application in green marketing is garnering growing interest—particularly in light of rising consumer demand for environmentally friendly products. However, research exploring consumer responses to AI-powered service interfaces in the context of green consumption remains limited. This study addresses that gap by examining how the type of service agent (AI vs. human) influences consumer satisfaction with green product purchases. Across three studies involving a total of 766 participants, data were collected via structured questionnaires using random sampling. Results show that consumers interacting with AI agents report higher satisfaction with their green purchases than those served by human agents. This effect is mediated by the perceived level of self-effort invested in the transaction. Furthermore, environmental consciousness moderates this relationship: the satisfaction advantage of AI agents diminishes among consumers with high environmental consciousness. These findings provide new theoretical insights into consumer–AI dynamics in green marketing and offer actionable guidance for both researchers and practitioners aiming to enhance green consumption experiences.