> Markdown version of [/jobs/ext/3738852-stem-researcher-ai-trainer](https://www.wearedevelopers.com/jobs/ext/3738852-stem-researcher-ai-trainer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md).

---

# STEM Researcher - AI Trainer

- **Company:** Mercor
- **Location:** Madrid, Spain (Remote available)
- **Salary:** €104,000.0
- **Contract:** Permanent contract
- **Skills:** Training Data, Artificial Intelligence, Agentic-AI
- **Published:** October 15, 2026
- **Apply:** https://www.adzuna.es/details/5928660887

## About the Role

Must-Have

 * 5+ years as a scientist or engineer in research or industry.
 * Native or fluent in Spanish.
 * Degree from a top-20 university in Spain.
 * Comfortable with quantitative analysis, technical documentation, and data-heavy problem solving.

Preferred

 * Master's or PhD.

## Description

* Develop workspaces and files to train AI agents on realistic professional tasks.
 * Write prompts and create grading rubrics based on real STEM work in Spain.
 * Evaluate the accuracy and depth of AI-generated content to strengthen reasoning and rigor in model outputs.
 * Provide clear, structured feedback to AI research teams to improve training data quality and downstream performance.
 * Work independently and asynchronously to meet deadlines while improving AI model performance., PS: Our team reviews applications daily. Please complete your AI interview and application steps to be considered for this opportunity.