OperationsMarch 5, 20261 min read
Building Annotation Teams That Scale: Lessons from 48K+ Contributors
How to recruit, train, and manage a distributed annotation workforce at scale.
By Tbrain Team
The 48K Contributor Challenge
Managing 48,000+ contributors across 17 countries is an engineering problem.
Recruitment: Quality Over Quantity
- Domain-specific tests — medical annotators take medical exams
- Trial tasks — 50 examples scored against gold standard
- Continuous evaluation — calibration tasks in regular workflow
Training: The Guideline-First Approach
Every project starts with 2 weeks of guideline development. No exceptions.
Management: Real-Time Visibility
- Per-annotator quality dashboards
- Anomaly detection — flagging sudden quality drops
- Automated pre-screening — AI catches 60-70% of obvious errors
The best annotation teams are engineering teams that happen to work with human data.
