English-Speaking AI Data Evaluation Specialist | Large Language Models

CloserHire is partnering with a leading global customer experience company to recruit English-speaking AI Data Evaluation Specialists for an innovative artificial intelligence project based in Lisbon, Portugal. If you’re passionate about AI, language technology, and data quality, this is a unique opportunity to contribute to the development of next-generation Large Language Models (LLMs). You’ll work with cutting-edge AI systems by reviewing, evaluating, and improving AI-generated responses, helping create safer, more accurate, and more reliable conversational experiences for millions of users worldwide.

Language required: English

Highlights:

• Salary up to 1020 EUR
• Private health insurance
• Meal vouchers / allowance

Responsibilities:

• Review and evaluate AI-generated responses using detailed annotation and quality guidelines
• Label and annotate language model outputs with accuracy and consistency
• Assess AI-generated content for quality, relevance, factual accuracy, safety, and policy compliance
• Apply complex annotation guidelines across a wide variety of scenarios and content types
• Identify inconsistencies, edge cases, and potential model issues, escalating when appropriate
• Analyze structured text, datasets, and AI-generated content to support model improvement
• Deliver high-quality work while consistently meeting productivity, quality, and accuracy targets
• Maintain strict confidentiality and comply with all project standards, security requirements, and internal procedures
• Contribute directly to the ongoing training and improvement of advanced AI systems through detailed evaluations and feedback 24/7 rotating schedule (Monday to Sunday) with 2 rotational days off

Qualifications:

• Native-level fluency in English
• Good command of English (B2 level or above)
• Strong understanding of Generative AI, Large Language Models (LLMs), and AI evaluation methodologies
• Previous experience in AI data annotation, LLM evaluation, Reinforcement Learning from Human Feedback (RLHF), Supervised Fine-Tuning (SFT), Quality Assurance, Content
• Labeling, Trust & Safety, or similar analytical roles is highly desirable
• Excellent analytical thinking and attention to detail
• Ability to interpret and consistently apply complex written guidelines and policies
• Strong reading comprehension and written communication skills
• Comfortable working with structured text, datasets, and AI-generated content
• Ability to work efficiently in a fast-paced, quality-driven environment while meeting performance targets
• Professional, objective, and capable of handling confidential information with discretion

Benefits:

• Office-based position in Lisbon, Portugal
• Comprehensive onboarding and specialized training in AI evaluation processes
• Opportunity to work on one of the world’s most advanced artificial intelligence projects
• International and multicultural working environment
• Career development opportunities within the rapidly growing AI industry
• Private health insurance
• Meal allowance Ongoing learning and professional development
• Modern office facilities with a collaborative team culture Unique opportunity to shape the future of generative AI and language technologies

Relocation:
No relocation support is offered for this role — candidates must already live in the job's country/city, or already hold valid work authorization for it.