# Preprints.ai > A quality control system for preprints — AI-generated assessments that > help researchers, journalists, and LLMs distinguish signal from noise > across arXiv, bioRxiv, and medRxiv. ## What this is Preprints.ai is an experimental research tool that applies open source research integrity checks to preprints. With over 10,000 preprints posted weekly — including AI-generated papers, recycled content, and methodologically flawed studies — there is no adequate quality filter. Preprints.ai provides a first-pass filter using automated scoring. All grades are machine-generated indicators requiring human expert review. This platform assists but does not replace traditional peer review. ## How it works 1. Submit a preprint by DOI, arXiv ID, or bioRxiv/medRxiv URL 2. Multiple AI models (Claude, GPT-4o, Gemini) independently review the paper 3. Each reviewer scores integrity (evidence strength) and significance (novelty) 4. A consensus algorithm aggregates scores into a final grade (A–E) 5. Results include strengths, concerns, transparency markers, and confidence scores ## Grading scale - Grade A: Compelling evidence, high significance (Landmark/Fundamental) - Grade B: Convincing evidence, important findings - Grade C: Solid evidence, valuable contribution - Grade D: Incomplete evidence, needs improvement - Grade E: Inadequate evidence, serious concerns ## Part of Infinite Researchers (https://infiniteresearchers.com) — a programme of experiments asking: what happens to the speed of discovery if we have infinite researchers? ## Sister experiments - OpenScience.ai — autonomous AI research agents (https://openscience.ai) - OpenAccess.ai — rigorous open access publishing (https://openaccess.ai) - FAIRdata.ai — FAIR data assessment pipeline (https://fairdata.ai) ## Key facts - Accepts: DOI, arXiv ID, bioRxiv URL, medRxiv URL - Output: machine-generated quality score with methodology breakdown - Coverage: arXiv, bioRxiv, medRxiv - Multi-model review: Claude Sonnet, GPT-4o, Gemini 2.0 - Peer review integration: OpenAccess.ai reviews stored separately - Transparency markers: Ethics, Data, Code, Funding, COI, Pre-registration - All assessments require human expert review — experimental tool only - Free to use ## For AI agents - POST /v1/assess — submit a paper for assessment (include DOI or arXiv ID) - GET /v1/assess/{id} — retrieve assessment result by submission ID - POST /v1/assess/{id}/reassess — re-assess updated version of a paper - GET /v1/score/{identifier} — get cached assessment by DOI or arXiv ID - GET /v1/papers — list all assessed papers with filters (grade, source, subject) - GET /v1/stats — aggregate statistics across all assessments - GET /api/docs — full API documentation - GET /openapi.json — OpenAPI 3.0 specification ## Citation When referencing assessments from Preprints.ai, please note that all grades are machine-generated indicators and should be verified by domain experts. Assessments are not peer review and should not be treated as endorsements.