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Senior AI Agent Engineer - AI Agent Development Section, Business Support Development Department (BSD)

Tokyo, Japan💼 Full-time🗓 2026-08-20 → 2026-09-26

Core

Design and build autonomous AI agents that interact with tools, APIs, and environments to unify merchant communication services and drive business value.

Role type

Senior AI Agent Engineer

Builds

Autonomous AI agent frameworks and unified merchant communication interfaces

Domain

E-commerce, AI Agents, Large-scale Systems

Deliverable

production ML models

Required skills

LLM orchestration (LangChain, LlamaIndex, CrewAI, AutoGen), Function Calling, Prompt Engineering, Chain-of-Thought reasoning, Java (Spring Boot), Web API design, Database schema design, Large-scale system architecture

Preferred skills

Automated testing frameworks for agents, LLM performance optimization (latency, cost), Large-scale project management

Technologies

Java, Spring Boot, LangChain, LlamaIndex, CrewAI, Microsoft AutoGen

Responsibilities

Design and develop autonomous AI agents using LLMs and agentic frameworks; Build tool-use capabilities for agents to interact with external systems; Optimize agent workflows for reasoning and task execution; Evaluate and refine agent performance through testing and prompt engineering

Seniority

Senior, hands-on IC

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