RAG API — upload documents, ask questions, get cited answers
The /rag namespace handles the full retrieval-augmented-generation pipeline — upload, chunk, embed, search, and generate a cited answer — as four ordinary REST endpoints, no separate infrastructure to manage.
No credit card · Free tier forever · X-API-Key header auth
What's included in /rag
Upload and auto-processing
POST a text document and it's automatically chunked and embedded — no separate ingestion pipeline to build.
Pure semantic search
Query your documents and get back the most relevant chunks with similarity scores, no generation step required.
Cited chat answers
Ask a natural-language question and get a generated answer with numbered citations back to the source chunks.
Built on pgvector
Vectors live in Postgres via pgvector — no separate vector database to provision or pay for.
Per-user document isolation
Every document and query is scoped to your account — your data never mixes with another customer's.
Start using the RAG API today
Free tier — 500 calls/month, no credit card. Upgrade when you need more.
Frequently asked questions
What plan is required?
Growth plan and above — /rag is the one namespace gated above Free, because every call has a real upstream embedding/generation cost.
Does it support PDF uploads?
Not yet — v1 supports plain text. PDF support is a planned addition.
What powers the embeddings and generation?
OpenAI's text-embedding-3-small for embeddings and GPT-4o mini for generation, with vectors stored in Supabase via pgvector.
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