AI Training Jobs in Brazil 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.
Skills
Human ResourcesTechnology, Information and Internet