# OpenTrain AI - Full Documentation > OpenTrain is the open talent network for AI training and data labeling. AI teams can hire human evaluators, RLHF reviewers, red-teamers, annotators, and domain experts directly, or use OpenTrain managed service when they want the project run for them. Pricing is published: 10% self-service marketplace fee plus a $9.95 new-contract fee, and 20% managed service. Website: https://www.opentrain.ai Contact: contact@opentrain.ai LinkedIn: https://www.linkedin.com/company/opentrain/ X/Twitter: https://x.com/OpenTrainAI ## About OpenTrain OpenTrain is a talent marketplace that connects AI companies with AI Trainers and Data Labelers. The platform helps teams find qualified humans for AI training tasks, from LLM evaluation and RLHF preference data to image annotation and document labeling. Approved proof points: - Published pricing: 10% self-service marketplace fee plus a $9.95 new-contract fee, and 20% managed service fee. - No hidden markups. - Live-proctored testing plus human interviews across 40+ domains. - Talent works in the customer's existing annotation or internal tools, including Label Studio, CVAT, Argilla, Roboflow, Kili, SuperAnnotate, and other platforms. - Freelancer work history aggregates across 20+ platforms. ### How It Works 1. **Post a Job**: Describe your AI training project, required skills, and tools. Free to post. 2. **Review Proposals**: Review qualified applicants and proposals for AI training and data labeling work. 3. **Hire and Manage**: Bring talent into the annotation or evaluation tools you already use. No vendor lock-in. OpenTrain experts work in your tools, not ours. Learn more: https://www.opentrain.ai/how-it-works/ ### Two Ways to Work with OpenTrain **Self-Service Platform**: Post a project and hire AI Trainers directly. You manage the team in your own tools. OpenTrain's self-service fee is 10%. **Managed Service**: For large or complex projects. OpenTrain recruits, onboards, and manages a dedicated team inside your tools. OpenTrain's managed service fee is 20%. Learn more about Managed Service: https://www.opentrain.ai/managed-service/ Request a quote: https://www.opentrain.ai/get-a-quote/ ### Pricing - **Self-Service**: 10% fee. - **Managed Service**: 20% fee. - **Markup policy**: No hidden markups. No custom quotes required to get started. Full pricing details: https://www.opentrain.ai/pricing/ --- ## Jobs Board (for AI Trainers) OpenTrain aggregates remote AI-training and data-labeling jobs from 20+ platforms into a single board. Every role is remote, and candidates apply with a free OpenTrain account. Freelancer work history aggregates across those platforms into one profile. - Browse all jobs: https://www.opentrain.ai/jobs/ - Jobs by category: https://www.opentrain.ai/jobs/categories/ (Generative AI & RLHF, coding & software, transcription and translation, image and video annotation, audio and speech, search evaluation, medical, legal and finance, data collection, writing, general annotation) - Jobs by subject-matter domain: https://www.opentrain.ai/jobs/domains/ (medicine, law, software engineering, finance, mathematics, languages, and 70+ more specialties) - Jobs by location: https://www.opentrain.ai/jobs/locations/ (countries where roles are currently open) - Live jobs directory for agents: https://www.opentrain.ai/jobs/llms.txt (machine-readable index of open roles by facet plus a sample of current listings, updated continuously) Each facet page carries evergreen guidance (what the work involves, skills, how hiring works, FAQ) plus the live listings. Individual job pages emit schema.org JobPosting structured data for Google for Jobs. --- ## LLM & Agent Solutions These solutions support teams building, evaluating, and improving large language models and AI agents. ### LLM Evaluation Hire expert evaluators for golden dataset creation, pairwise ranking, rubric-based scoring, judge model validation, and evaluation pipeline QA. Evaluators assess factual accuracy, reasoning quality, safety compliance, and instruction following. URL: https://www.opentrain.ai/solutions/llm-evaluation/ ### RLHF & Preference Data Hire domain experts for pairwise preference ranking, multi-criteria scoring, response rewrites, failure tagging, and preference data QA. Essential for training reward models and improving LLM output quality through human feedback. URL: https://www.opentrain.ai/solutions/rlhf-and-preference-data/ ### Red Teaming Hire security specialists and domain experts for jailbreak testing, prompt injection attempts, policy bypass detection, data leakage probing, and adversarial evaluation. Critical for identifying vulnerabilities before deployment. URL: https://www.opentrain.ai/solutions/ai-red-teaming/ ### Hallucination Audits Hire fact-checkers and domain experts for claim verification, citation checking, severity scoring, and hallucination taxonomy labeling. Ensures LLM outputs are grounded in factual information. URL: https://www.opentrain.ai/solutions/hallucination-audits/ ### Supervised Fine-Tuning Hire experts for instruction data creation, domain-specific verification, synthetic data quality assurance, and training dataset curation. Covers prompt-response pair authoring and dataset cleaning. URL: https://www.opentrain.ai/solutions/supervised-fine-tuning/ ### Code Generation Review Hire programmers for code verification, RLHF ranking of code outputs, bug detection, security review, and code quality assessment. Supports training coding assistants and code generation models. URL: https://www.opentrain.ai/solutions/code-generation-review/ ### Function Calling Hire specialists for tool selection annotation, argument labeling, multi-step trace verification, error recovery labeling, and function calling evaluation. Essential for training AI agents that use tools. URL: https://www.opentrain.ai/solutions/function-calling/ ### Agent Simulations Hire task designers, trajectory reviewers, and gold-trace operators for scenario design, gold trajectory creation, rollout evaluation, failure tagging, and agent behavior assessment across web, OS, and custom sandboxes. URL: https://www.opentrain.ai/solutions/agent-simulations/ ### Computer Use Agent Training Hire specialists to create trajectory data and perform evaluation for browser and desktop agents. Covers UI interaction traces, task completion verification, and cross-platform testing. URL: https://www.opentrain.ai/solutions/computer-use-agent-training/ ### Reasoning Problem Creation Hire mathematicians, scientists, and programmers to create original problems with step-by-step solutions in math, code, logic, and science domains. Used for training and benchmarking reasoning capabilities. URL: https://www.opentrain.ai/solutions/reasoning-problem-creation/ ### Reasoning Step Verification Hire experts to provide step-level correctness labels for training process reward models (PRMs). Each step in a reasoning chain is labeled for logical validity and factual accuracy. URL: https://www.opentrain.ai/solutions/reasoning-step-verification/ ### RL Environment Design Hire specialists to design reward functions, create training scenarios, and QA environments for reinforcement learning agents. Covers reward shaping, curriculum design, and environment validation. URL: https://www.opentrain.ai/solutions/rl-environment-design/ ### Multilingual AI Training Hire native speakers for RLHF, evaluation, prompt writing, translation quality assessment, and cultural accuracy checking. URL: https://www.opentrain.ai/solutions/multilingual-ai-training/ --- ## Data Labeling Solutions These solutions support teams building computer vision, NLP, and multimodal AI models. ### Image Annotation Hire annotators for bounding boxes, polygons, keypoints, image classification, attribute labeling, and quality assurance. Covers object detection, pose estimation, and scene understanding tasks. URL: https://www.opentrain.ai/solutions/image-annotation/ ### Video Annotation Hire annotators for object tracking, temporal event labeling, action recognition, scene classification, and annotation QA. Supports autonomous driving, surveillance, sports analytics, and media applications. URL: https://www.opentrain.ai/solutions/video-annotation/ ### Document Annotation Hire specialists for entity extraction, table structure labeling, grounded question answering, document classification, and OCR verification. Supports document AI and information extraction. URL: https://www.opentrain.ai/solutions/document-annotation/ ### Segmentation Hire annotators for pixel-level semantic segmentation, instance segmentation, and panoptic segmentation. Covers automotive, medical, agricultural, and industrial applications. URL: https://www.opentrain.ai/solutions/segmentation/ ### Text Annotation Hire linguists and domain experts for named entity recognition, sentiment analysis, text classification, relation extraction, and content moderation. URL: https://www.opentrain.ai/solutions/text-annotation/ ### Medical Imaging Annotation Hire clinicians and imaging specialists for segmentation and labeling of CT, MRI, pathology slides, X-ray, ultrasound, and other medical imaging modalities. HIPAA-aware workflows available. URL: https://www.opentrain.ai/solutions/medical-imaging-annotation/ ### Satellite Imagery Annotation Hire GIS specialists for mapping-grade labels for geospatial AI and Earth observation. Covers land use classification, object detection, change detection, and infrastructure mapping. URL: https://www.opentrain.ai/solutions/satellite-imagery-annotation/ ### Point Cloud Annotation Hire 3D annotation specialists for cuboid labeling, point cloud segmentation, object tracking, sensor fusion, and LiDAR data processing. Supports autonomous vehicles and robotics. URL: https://www.opentrain.ai/solutions/point-cloud-annotation/ ### Speech and Audio Labeling Hire linguists for audio transcription, speaker diarization, audio event labeling, emotion detection, and quality assessment across multiple languages and accents. URL: https://www.opentrain.ai/solutions/speech-and-audio-labeling/ ### Time Series Annotation Hire domain experts for event labeling, anomaly detection, pattern classification, and temporal segmentation across sensor data from manufacturing, healthcare, finance, and IoT applications. URL: https://www.opentrain.ai/solutions/time-series-annotation/ --- ## Agent and Developer Entry Points OpenTrain publishes machine-readable entry points for agents, answer engines, and developer teams. - App llms.txt: https://app.opentrain.ai/llms.txt - Docs llms.txt: https://www.opentrain.ai/docs/llms.txt - Docs llms-full.txt: https://www.opentrain.ai/docs/llms-full.txt - Jobs board llms.txt: https://www.opentrain.ai/jobs/llms.txt (live directory of open AI-training and data-labeling jobs by category, subject-matter domain, country, and language, plus a sample of current roles) - Public OpenAPI spec: https://app.opentrain.ai/api/public/v1/openapi.json - Official CLI package: `@opentrain-ai/cli` - Official MCP package: `@opentrain-ai/mcp` The app `llms.txt` documents agent registration, job drafts, publishing, proposals, hiring, contracts, milestones, messages, webhooks, credits, and updates. Hiring and money movement are human co-signed: an API, CLI, or MCP call can request a hire, fund a milestone, or release payment, but a signed-in human must confirm the money-moving action. --- ## Additional Service Pages ### Hire Freelance Data Labelers Find and hire freelance data labelers for annotation or labeling projects. Browse profiles, check skills and tool expertise, and hire directly. URL: https://www.opentrain.ai/hire-freelance-data-labelers/ ### Data Labeling Solutions Overview Comprehensive overview of data labeling solutions for computer vision, NLP, audio, and multimodal AI projects. URL: https://www.opentrain.ai/data-labeling-solutions/ ### LLM & Agent Solutions Overview Overview of solutions for LLM evaluation, RLHF, red teaming, fine-tuning, and AI agent training. URL: https://www.opentrain.ai/llm-agent-solutions/ ### Data Labeling Outsourcing Marketplace Outsource data labeling to vetted providers and freelancers. Compare providers, read reviews, and find the right team for your project. URL: https://www.opentrain.ai/data-labeling-outsourcing-marketplace/ ### List Your Data Labeling Company Data labeling companies can list their services on the OpenTrain marketplace to reach AI teams looking for annotation providers. URL: https://www.opentrain.ai/list-your-data-labeling-company/ --- ## Supported Integrations OpenTrain experts work in the customer's existing annotation or internal tools. Supported integrations include: - **Label Studio** (https://www.opentrain.ai/integrations/label-studio/) — Open-source data labeling platform - **Roboflow** (https://www.opentrain.ai/integrations/roboflow/) — Computer vision annotation and model training - **AWS SageMaker Ground Truth** (https://www.opentrain.ai/integrations/aws-sagemaker-groundtruth/) — Amazon's managed data labeling service - **CVAT** (https://www.opentrain.ai/integrations/cvat/) — Open-source annotation tool for computer vision - **Scale Studio** (https://www.opentrain.ai/integrations/scale-ai/) — Enterprise data labeling platform - **SuperAnnotate** (https://www.opentrain.ai/integrations/superannotate/) — AI-powered annotation platform - **Encord** (https://www.opentrain.ai/integrations/encord/) — Data-centric AI platform - **Argilla** (https://www.opentrain.ai/integrations/argilla/) — Open-source feedback and evaluation tool for LLMs - **Dataloop** (https://www.opentrain.ai/integrations/dataloop/) — Data management and annotation platform - **Kili Technology** (https://www.opentrain.ai/integrations/kili-technology/) — Data labeling and quality management - **Prodigy** (https://www.opentrain.ai/integrations/prodigy/) — Annotation tool by Explosion AI - **Snorkel AI** (https://www.opentrain.ai/integrations/snorkel-ai/) — Programmatic labeling and data-centric AI - **Supervisely** (https://www.opentrain.ai/integrations/supervisely/) — Computer vision platform - **Datasaur** (https://www.opentrain.ai/integrations/datasaur/) — NLP and text annotation platform - **Datature** (https://www.opentrain.ai/integrations/datature/) — End-to-end computer vision platform - **Your Custom Tool** (https://www.opentrain.ai/integrations/custom-tool/) — Bring your own annotation platform; OpenTrain experts work in whatever tools you use --- ## AI Glossary OpenTrain maintains a comprehensive glossary of 439 AI and machine learning terms. Topics covered include machine learning fundamentals, neural network architectures, natural language processing, computer vision, reinforcement learning, data annotation methodology, AI safety, and more. Each entry includes a definition, detailed explanation, and practical example. Browse the glossary: https://www.opentrain.ai/glossary/abductive-reasoning/ --- ## Contact - **Email**: contact@opentrain.ai - **Contact Page**: https://www.opentrain.ai/contact/ - **Get a Managed Service Quote**: https://www.opentrain.ai/get-a-quote/ - **Create Account**: https://app.opentrain.ai/?key=signup - **Sign In**: https://app.opentrain.ai/?key=login