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The condition characterized by a painful, recurrent vesicular eruption of mucocutaneous surfaces is herpes simplex. This viral infection, caused by the herpes simplex virus (HSV), often presents as clusters of fluid-filled blisters that can be found on the lips, mouth, and other mucosal surfaces. The vesicular lesions are typically painful and can recur due to factors such as stress, illness, or immunosuppression.

Herpes simplex infections can manifest as oral herpes (cold sores) or genital herpes, both of which are known for their recurrent nature. The characteristic presentation of painful vesicles and ulcers makes it distinct amongst other skin conditions or infections.

Other options such as varicella zoster can also cause vesicular eruptions but are more systemic and typically present as widespread lesions associated with chickenpox or shingles, rather than recurrent localized outbreaks. Contact dermatitis is characterized by rash due to an allergic reaction or irritation, not recurrent vesicular lesions, and impetigo is a bacterial infection leading to crusted sores, primarily in children, rather than painful vesicular eruptions. Thus, herpes simplex is the most fitting diagnosis for the given description.