Brazilian Portuguese/English Bilingual AI Data Annotator & Evaluator (Remote, Hourly Contractor)

CNTXT AI; São Paulo; Remote; BRL 174,000 - 417,000; Part time

Job summary

CNTXT AI is seeking a senior Brazilian Portuguese localization contractor to support AI data and language projects on a fully remote, hourly basis. You will apply advanced localization judgment across data annotation, LLM evaluation, content generation, and localization QA while maintaining strong English proficiency to interpret prompts and guidelines.

The ideal candidate holds a Bachelor's degree and demonstrates exceptional editorial judgment, attention to detail, and the ability to identify

Qualifications

• Bachelor's degree or higher in translation, linguistics, localization, or related field.
• Native or near-native Brazilian Portuguese with strong writing/editing skills.
• Minimum C1 English proficiency for interpreting prompts and guidelines.
• Excellent editorial judgment in register, tone, inclusivity, and cultural nuance.
• Ability to identify meaning drift, ambiguity, locale inconsistencies, and to explain corrections clearly in writing.
• Ability to rigorously fact-check localized content using reliable sources and consistent reasoning.

Responsibilities

• Data annotation: labeling, classifying, and structuring documents, tables, and other content to support AI training datasets.
• LLM evaluation: reviewing AI-generated responses for accuracy, reasoning quality, coherence, and cultural/linguistic appropriateness.
• Content generation: writing high-quality prompts and model responses, or recording high-quality voice samples for AI learning.
• Localization QA: ensuring terminology, tone, cultural nuance, and locale-specific details are consistently accurate across outputs.

Skills

Brazilian Portuguese proficiency

English proficiency

Education

Bachelor's degree or higher

Job description

This is a fully remote, hourly contractor role supporting AI data and language projects on a project-based, flexible hour basis. Project scopes vary and may include:

Data annotation: labeling, classifying, and structuring documents, tables, and other content to support AI training datasets.

LLM evaluation: reviewing AI-generated responses for accuracy, reasoning quality, coherence, and cultural/linguistic appropriateness.

Content generation: writing high-quality prompts and model responses, or recording high-quality voice samples, to guide AI learning across diverse topics.

Localization QA: ensuring terminology, tone, cultural nuance, and locale-specific details (units, references, names, dates) are consistently accurate across outputs.

You will apply senior-level Brazilian Portuguese localization and translation judgment alongside minimum C1 English proficiency to ensure terminology, tone, and cultural nuance are consistently accurate across use cases.

Profile Requirements

Bachelor's degree or higher, preferably in Translation, Linguistics, Localization, Communications, or a related field.

Native or near-native Brazilian Portuguese proficiency with strong writing and editing skills.

Minimum C1 English proficiency (reading/writing) for interpreting prompts, source materials, and evaluation guidelines.

Excellent editorial judgment in register, tone, punctuation, inclusivity, and cultural nuance, with extreme attention to detail.

Ability to identify meaning drift, ambiguity, locale inconsistencies, and subtle errors, and to explain corrections clearly in writing.

Ability to rigorously fact-check localized content (units, references, names, dates) using reliable sources and consistent reasoning.

Ability to identify reasoning gaps, methodological errors, and unclear explanations even when language is fluent.

Reliable, self-directed, and able to deliver consistent quality with clear communication and responsiveness across time zones.

Preferred Experience

Professional localization or translation experience.

Previous experience with AI data training, annotation, or evaluation.

Familiarity with MQM/LQA concepts (severity, category, and root-cause thinking) for consistent quality decisions.

Familiarity with CAT tools and QA workflows.

About CNTXT AI

CNTXT AI builds artificial intelligence products and data solutions with a focus on making AI accurate, safe, and globally relevant for impact. Our work spans data services, custom AI solutions, and proprietary AI products, with deep expertise in Arabic-native and secure, sovereign solutions.