Sr AI Engineer

T-Mobile USA; Bellevue (WA); On-site; USD 180,000 - 280,000; Full time

Job summary

T-Mobile USA is seeking a Senior AI Engineer to architect and optimize agentic AI systems powering the next generation of customer service. You will design and deploy AI that coordinates across models, APIs, and tools to deliver reliable, production-grade workflows and intuitive customer interactions.

In this role, you will apply prompt engineering, model fine-tuning, evaluation frameworks, and system orchestration to improve accuracy, reliability, and reasoning across millions of conversations,

Qualifications

• Strong proficiency in Python and OO design.
• Experience building Generative AI applications and LLMs.
• Experience with LangGraph/LangChain.
• Experience with RESTful APIs and FastAPI.
• Experience with Azure/AWS/GCP.
• Knowledge of embeddings, vector databases, and retrieval.
• Experience with DevOps and CI/CD.

Responsibilities

• Design, develop, and deploy scalable, production-grade Generative AI applications, LLM-powered solutions, and agentic AI systems to support enterprise business operations and customer service automation.
• Architect and implement AI agents and multi-agent orchestration workflows using LangGraph, LangChain, or equivalent frameworks.
• Develop Retrieval-Augmented Generation (RAG) solutions leveraging embeddings, vector databases, semantic search, and enterprise knowledge sources.
• Build and integrate RESTful APIs, MCP connectors, and enterprise data services for secure AI interactions.
• Optimize AI performance via prompt engineering, model selection, retrieval tuning, fine-tuning, and efficient inference strategies.
• Establish AI evaluation frameworks to measure accuracy, hallucination rates, reliability, latency, and cost efficiency.
• Develop cloud-native AI solutions using Azure, AWS, or equivalent platforms, with containerization and automated deployment.
• Implement security, governance, and responsible AI practices.
• Establish observability, logging, monitoring, and troubleshooting for AI apps in production.
• Collaborate with cross-functional teams to integrate AI enhancements into production systems.
• Conduct design reviews, participate in code reviews, mentor engineers, and contribute to best practices.
• Research emerging AI technologies and stay current to identify opportunities for innovation.

Skills

Python

REST APIs

Generative AI

Agentic AI

LangChain

LLMs

Embeddings

Vector DB

Cloud

CI/CD

Tools

LangGraph

FastAPI

Azure

AWS

GCP

Job description

At T-Mobile, we invest in YOU! Our Total Rewards Package ensures that employees get the same big love we give our customers. All team members receive a competitive base salary and compensation package - this is Total Rewards. Employees enjoy multiple wealth-building opportunities through our annual stock grant, employee stock purchase plan, 401(k), and access to free, year-round money coaches. That's how we're UNSTOPPABLE for our employees!

Engineer the intelligent core of T-Mobile's next-generation customer experience.

We're seeking a Senior AI Engineer to architect and optimize the agentic AI systems driving the evolution of customer service. You'll design AI that performs with precision and coordinates across models, internal APIs, and third-party tools to create reliable, production-grade workflows and intuitive customer interactions.

Using advanced techniques such as prompt engineering, model fine-tuning, evaluation frameworks, and system-level orchestration, you'll improve the accuracy, reliability, and reasoning capabilities of AI across the enterprise. Working closely with engineering, product, and operations teams, you'll bring these innovations to life in resilient, fault-tolerant environments supporting millions of real-world customer conversations.

This is an opportunity to help define the AI foundation of the Un-carrier and build intelligent systems that set a new standard for customer experience. If you're passionate about engineering quality, solving complex problems, and making a meaningful customer impact, we invite you to apply.

RESPONSIBILITIES

• Design, develop, and deploy scalable, production-grade Generative AI applications, LLM-powered solutions, and agentic AI systems to support enterprise business operations and customer service automation.
• Architect and implement sophisticated AI agents and multi-agent orchestration workflows using modern frameworks such as LangGraph, LangChain, or equivalent technologies.
• Develop Retrieval-Augmented Generation (RAG) solutions leveraging embeddings, vector databases, semantic search, and enterprise knowledge sources.
• Build and integrate RESTful APIs, Model Context Protocol (MCP) connectors, and enterprise data services to enable secure AI interactions with internal and external systems.
• Optimize AI performance through prompt engineering, model selection, retrieval optimization, fine-tuning, and efficient inference strategies to enhance customer service automation.
• Design and implement AI evaluation frameworks to measure accuracy, hallucination rates, reliability, latency, throughput, and cost efficiency, ensuring alignment with strategic objectives and customer satisfaction goals.
• Develop cloud-native AI solutions using Azure, AWS, or equivalent platforms, incorporating containerization, automated deployment, and scalable architectures.
• Implement security, governance, and responsible AI practices, including authentication, authorization, data privacy, prompt injection protection, and enterprise compliance requirements.
• Establish observability, logging, monitoring, and troubleshooting capabilities for AI applications and agentic workflows in production environments.
• Collaborate with cross-functional engineering, architecture, product, cybersecurity, and business teams to ensure seamless integration of AI-driven enhancements into production systems.
• Conduct technical design reviews, participate in code reviews, mentor engineers, and contribute to reusable engineering standards and best practices.
• Research and evaluate emerging AI technologies, open-source frameworks, and industry advancements to stay current with the latest methodologies applicable to customer service and to identify opportunities for innovation and continuous improvement.
• Perform other duties and projects as assigned by business management.

Skills

REQUIRED

• Programming: Strong proficiency in Python, software engineering principles, and object-oriented programming.
• API Development: Experience designing, developing, securing, and integrating RESTful APIs using frameworks such as FastAPI or equivalent.
• Generative AI and LLMs: Hands-on experience building applications using large language models, prompt engineering, structured outputs, function calling, and tool integration.
• Agentic AI: Experience developing AI agents, tool-calling workflows, and orchestration solutions using LangGraph, LangChain, or similar frameworks.
• RAG and Data Management: Knowledge of embeddings, vector databases, semantic retrieval, document processing, and data integration.
• Cloud Computing: Experience developing and deploying applications on Azure, AWS, or Google Cloud.
• Software Engineering and DevOps: Proficiency with Git, CI/CD pipelines, automated testing, and production software development practices.
• System Architecture: Ability to design scalable, secure, reliable, and maintainable distributed applications.
• Data Analysis and Modeling: Strong analytical skills