mockMvc.perform(MockMvcRequestBuilders.get("/api"))
                .andDo(MockMvcResultHandlers.print())
                .andExpect(MockMvcResultMatchers.status().isOk())
                .andExpect(MockMvcResultMatchers.jsonPath("$[0].currency").value("USD"))
                .andExpect(MockMvcResultMatchers.jsonPath("$[0].message.originalText").value("original text"))
                .andExpect(MockMvcResultMatchers.jsonPath("$[0].operations").isArray())
                .andExpect(MockMvcResultMatchers.jsonPath("$[0].operations[*].abc").value(Matchers.containsInAnyOrder("abc1", "abc2")));

Протестировать ваш jsonPath можно в сервисе https://jsonpath.com/