About the Role

We are looking for a junior Agentic AI Engineer to join our growing AI Factory and contribute to the design, development and scalling of intelligent agent systems. You will work at the intersection of applied AI and production engineering, building agentic architectures that deliver measurable business value across complex, multi-stakeholder environments.

This is a hands-on technical role for someone who thrives in ambiguity, moves fast between experimentation and production, and understands and communicates AI concepts clearly to both engineering teams and business stakeholders.

What You Will Do

Agentic Systems Development

• Contribute to the design and implementation of multi-agent systems, RAG pipelines and tool-augmented workflows.

• Work with frameworks such as LangChain and LangGraph to build and iterate on conversational and agentic workflows.

• Help integrate agent systems with enterprise data sources, APIs and external tools.

Observability, Testing & Reliability

• Instrument agent workflows using observability platforms such as Opik to trace execution, monitor tool calls and surface failure patterns.

• Write and maintain tests for agentic components: prompt regression tests, tool-level unit tests and integration tests for multi-step workflows.

• Participate in automated evaluation pipelines, including LLM-as-a-judge assessments and contribute to red-teaming exercises to identify unexpected agent behaviours.

• Learn to connect production traces to evaluation suites using real failures to improve system robustness iteratively.

Learning & Growth

• Stay curious about the evolving LLM and agent ecosystem: new frameworks, evaluation techniques, failure patterns, etc.

• Document your work clearly: architectures, experiments, findings and open questions.

• Contribute to cross-functional meetings by identifying collaboration opportunities and articulating the purpose and progress of your work.

What We Are Looking For

Required

• Proven hands-on experience designing and shipping LLM-based applications and agentic workflows.

• Familiarity with LLM evaluation methodologies (LLM-as-a-judge, automated pipelines, red-teaming).

• Solid Python skills with evidence of hands-on use (personal projects, coursework, or public repositories).

• Working experience with agentic AI frameworks: LangChain, LangGraph, or equivalent.

• Experience building RAG pipelines and integrating external tools and knowledge sources into agent systems.

• Comfort working with relational and non-relational databases and REST API development.

• Experience with software engineering fundamentals: Git, Docker, CI/CD and Agile workflows.

• Ability to communicate AI challenges, trade-offs, and solutions clearly to non-technical audiences.

Education

• Technical degree in Telecommunications, Computer Science, Software Engineering, or similar.

• A specialisation or internship in Data Science, AI, or ML is a plus.

• Full professional fluency in Spanish and English, with the ability to run meetings and workshops in multinational settings.

Nice to Have

• Experience with ML and data workflows: scikit-learn, pandas, feature engineering and anomaly detection.

• Exposure to AI-assisted development with coding agents.

Who You Are

You are intellectually curious and developing the rigour to know when a large language model is the right tool and when it is not. You take ownership of your work even when the path is unclear and you follow through from first experiment to shipped result. You engage confidently in cross-functional conversations, learning to bridge technical and product perspectives. You bring discipline and commitment to everything you build.

If you join Telefónica

You join almost 100 years of history, you join a team of 106 nationalities present in more tan 35 countries. You join a team that works to connect people wherever they are. We are leading the digital revolution with the enthusiasm of the first day in all our businesses, creating the best digital ecosystem for our clients: network, IoT, cloud, security, innovation etc. Here, at Telefónica you count with everything you need to be the best you. We need people like you that wants to take this challenge of creating the Telefónica of tomorrow.

Telefonica is committed to the new working ways. Under our proposition “Disconnect to Reconnect” we have applied the Digital Disconnection.

You join a company whose activity is governed by its code of ethics, Our Responsible Business Principles. We are looking for people who identify with them, who help us make decisions based on integrity, commitment and transparency and who are committed to ethical management, promoting fairer and more sustainable social and environmental development.

#WeAreInclusive

We strongly believe diverse and inclusive teams become more innovative and they achieve improved results. Telefonica aims to promote and guarantee a place for everyone, just the way we are: gender, age range, sexual orientation and/or identity, culture, creed, disability or any other personal condition.