Job Description

Career Opportunity for an AI Application Engineer in Japan! 

■ AI Application Engineer (English speaking position)

■ Company Overview

An e-commerce, fintech, digital content and communications company with more than 30,000 employees, and operations in 30 countries and regions.

■ Your Role and Responsibilities 

●You will lead the development of next-generation AI agents, work closely with business stakeholders, you will drive the system design, implementation, and production operations of autonomous AI agents that support both end users and accommodation partners.

What Makes This Role Unique

●Be a core member driving the design and development of next-generation AI agents powered by generative AI.

●Actively adopt and experiment with the latest LLMs, agent frameworks, and the Model Context Protocol (MCP) in AI agent development.

●Work on product development that leverages companies large-scale data assets.

●Be involved in designing and building data and AI platforms on cloud environments.

●Make a direct impact on the core features that are closely linked to business growth.

Key Responsibilities

●Design and develop AI agents for the use cases such as search, booking, and customer support, including orchestration across MCP, tools, and backend systems.

●Define functional and non-functional requirements for AI agents based on business needs and user pain points.

●Implement and continuously improve AI agent and MCP platforms using LLM APIs (e.g., OpenAI, Vertex AI, Azure OpenAI) and modern agent frameworks.

●Design context management through knowledge bases and RAG architectures, and integrate with internal and external APIs/systems (e.g., tool invocation, multi-agent communication).

●Define conversation-quality metrics, build automated evaluation and test cases, and continuously drive quality improvements based on user logs and feedback.

●Own deployment, monitoring, and troubleshooting in production environments, and plan A/B tests to to evaluate the effectiveness and improve the system.

●Establish and refine development processes (e.g., Docker, CI/CD), providing technical leadership to the team through code reviews, mentoring, and knowledge sharing.

■ Experience and Qualifications

●5+ years of experience developing systems that incorporate machine learning/AI.

●2+ years of experience leading projects end to end, from system design to production release, for systems using machine learning/AI 

●Hands-on experience developing AI agents/MCP using AI agent frameworks such as OpenAI Agent SDK, Google ADK, etc.

●Experience in context engineering to personalize AI agent behavior and optimize response quality.

●Experience designing evaluation frameworks for AI agents and automating evaluation workflows.

●Experience working in cross-functional teams.

●Experience validating impact based on the product KPIs, and driving continuous improvement through A/B testing.

■ Additional Preferred Qualifications
●Practical experience applying machine learning to real-world business problems, or an academic background in a related field

●Experience with DevOps / LLMOps practices (e.g., Docker, CI/CD).

●Development experience on cloud infrastructure platforms such as Google Cloud Platform (GCP).

■ Good Reasons to Join

● Hybrid position in Japan

● Work with International team members

■ Work Location

Tokyo, Japan

Details will be provided during the meeting.