Base URL
Authentication
No authentication is required. The API is free and open.Rate limiting
Requests are rate limited to 200 requests per minute per IP address. Rate limit headers are included in every response:
If you exceed the limit, you’ll receive a
429 response.
POST /feedback has its own, lower limit: 5 requests per minute and 10 per 15 minutes. See Feedback.
Error responses
All errors follow RFC 9457 Problem Details withContent-Type: application/problem+json:
Caching
All responses includeCache-Control headers. Cloudflare’s CDN caches responses at the edge using s-maxage, so repeated requests are served from the nearest edge node without hitting the origin.
Static content (papers, paragraphs, audio, OG images) is immutable, so it’s cached aggressively. The random endpoint is never cached.
Paragraph ID formats
Many endpoints accept paragraph references in three auto-detected formats:RAG-optimized format
Paragraph endpoints support?format=rag to return a streamlined shape for AI/RAG pipelines:
GET /paragraphs/:ref?format=rag and GET /paragraphs/random?format=rag.
Feedback
Found a bug or a gap in these docs? Send it toPOST /feedback. No authentication required. See Feedback.