
AI Training Specialist (Brazil, Remote)
Rex.zone · United States
This listing has closed — view similar roles below.
- Hybrid
- Full-time
- $83,200 / year
- United States
Job highlights
- Train AI models using text and image data.
- Perform data labeling and quality assurance.
- Evaluate LLM outputs and computer vision data.
- Work remotely full-time in Brazil.
- Contribute to AI model improvement.
About the role
AI Training Specialist at Rex.zone
Rex.zone connects Brazil-aligned talent with remote, full-time AI training work supporting LLM and computer vision model improvement through high-quality data and evaluation signals.
About The Role
You will contribute to AI training workflows that turn raw text, images, and model outputs into supervised datasets and evaluation signals. Work includes data labeling, RLHF preference ranking, prompt evaluation, QA evaluation, and guideline-based review in asynchronous, quality-driven delivery.
What You’ll Do
- Create and apply annotation taxonomies and guidelines
- Label text and image data; perform named entity recognition and document classification
- Conduct RLHF comparisons and preference ranking
- Execute prompt evaluation and rubric-based scoring
- Complete QA evaluation, adjudication, and error analysis
- Validate training data quality via sampling and audits
- Track inter-annotator agreement, defect rates, and calibration outcomes
- Document decisions to support consistent evaluation and dataset versioning
Domains You May Support
NLP/LLM evaluation, content safety labeling, multilingual Portuguese/English tasks, and computer vision annotation (e.g., bounding boxes/segmentation), depending on project needs.
Requirements
- Mid-senior capability in structured evaluation and operational rigor
- Experience with data labeling or QA evaluation in production settings
- Comfort with ambiguity resolution and rubric adherence
- Strong written communication for guideline interpretation
- Familiarity with LLM evaluation concepts (helpfulness, factuality, toxicity, instruction following)
Compensation
Hourly range: $30–$50/hr (USD).
Quality is measured by audit accuracy, guidelines compliance, inter-annotator agreement, defect rates, and turnaround time.
Key skills/competency
- AI Training
- LLM Evaluation
- Computer Vision Annotation
- Data Labeling
- RLHF Preference Ranking
- Prompt Evaluation
- QA Evaluation
- Guideline Adherence
- Annotation Taxonomies
- Structured Evaluation
Skills & topics
- AI Training Specialist
- AI
- Machine Learning
- Data Labeling
- LLM
- Computer Vision
- NLP
- QA
- Remote
- Brazil
How to get hired
- Research Rex.zone's mission: Understand their focus on Brazil-aligned talent and AI model improvement.
- Tailor your resume: Highlight experience in data labeling, QA evaluation, and LLM concepts.
- Showcase operational rigor: Emphasize structured evaluation and adherence to guidelines.
- Prepare for technical questions: Be ready to discuss LLM evaluation metrics and annotation processes.
- Express interest in remote work: Confirm your ability to work effectively in a remote, quality-driven environment.
Technical preparation
Behavioral questions
Frequently asked questions
- What specific AI training tasks will an AI Training Specialist at Rex.zone perform?
- As an AI Training Specialist at Rex.zone, you will engage in a variety of tasks including data labeling for text and images, performing named entity recognition and document classification, conducting RLHF (Reinforcement Learning from Human Feedback) comparisons and preference rankings, executing prompt evaluations with rubric-based scoring, and completing QA evaluations and adjudication.
- What are the key qualifications for an AI Training Specialist role at Rex.zone?
- Successful candidates for the AI Training Specialist position at Rex.zone will demonstrate mid-senior capability in structured evaluation and operational rigor, possess experience with data labeling or QA evaluation in production settings, be comfortable with ambiguity resolution and rubric adherence, and have strong written communication skills for guideline interpretation. Familiarity with LLM evaluation concepts is also crucial.
- Is the AI Training Specialist position at Rex.zone a remote role?
- Yes, the AI Training Specialist position at Rex.zone is a remote role, specifically connecting Brazil-aligned talent with full-time AI training work opportunities.
- What is the compensation range for an AI Training Specialist at Rex.zone?
- The compensation for an AI Training Specialist at Rex.zone is on an hourly basis, ranging from $30 to $50 USD per hour.
- How does Rex.zone measure quality for AI Training Specialists?
- Rex.zone measures quality for AI Training Specialists based on several key performance indicators, including audit accuracy, compliance with guidelines, inter-annotator agreement, defect rates, and turnaround time.
- What kind of domains might an AI Training Specialist support at Rex.zone?
- Depending on project needs, an AI Training Specialist at Rex.zone might support domains such as NLP/LLM evaluation, content safety labeling, multilingual Portuguese/English tasks, and computer vision annotation, including tasks like bounding boxes and segmentation.
- What does RLHF mean in the context of an AI Training Specialist role?
- RLHF stands for Reinforcement Learning from Human Feedback. In the context of this role at Rex.zone, it involves conducting comparisons and preference rankings of model outputs to help train AI models more effectively based on human judgment.