In order for educators to be highly effective, they must be aware of how technology can enhance the teaching and learning process. Recently, augmented reality (AR) technology has gained significant attention and been widely adopted across disciplines. The aim of this study was to explore junior high school English teachers' perspectives and experiences regarding AR tool selection, their readiness and competencies, and the potential benefits and challenges of using augmented reality for vocabulary instruction. Implementing a qualitative case study design, seven junior high school English teachers from Semnan Province, Iran were purposively selected and interviewed. Thematic analysis of data yielded four principal findings. First, teachers' AR tool selection was primarily guided by accessibility considerations and engagement potential. Second, teacher readiness and competencies emerged as multidimensional, encompassing: (a) technological proficiency, (b) pedagogical knowledge for lesson adaptation, (c) content expertise, and (d) essential professional skills including creativity, adaptability, and effective collaboration/communication abilities. Third, analysis revealed three categories of benefits: (a) measurable learner outcomes; (b) enhanced learning experiences; and (c) improved interaction dynamics. Finally, implementation challenges were categorized across five domains: technical, logistical, teacher-related, student-related, and content-related. While offering practical insights for educators and policymakers, the study's findings are based on junior high school English teachers from Semnan Province, Iran. The qualitative depth ensures a rich understanding of this specific context, with findings that remain significant for comparable EFL environments. However, broader applicability would require further research with more diverse participant groups. These results highlight the need for targeted teacher training and improved AR resources for language education.