# AutoChunk API > AutoChunk turns business documents (PDF, HTML, DOCX, plain text) into AI-retrieval-ready chunks tagged with department, access level, source URL, and per-principal permissions. The data layer for permission-aware retrieval-augmented generation (RAG) — designed for legal, finance, healthcare, and enterprise B2B SaaS teams whose AI assistants must enforce who-sees-what at retrieval time. This is the marketing site at https://autochunkapi.com. The API itself, full developer documentation, interactive playground, and machine-readable specs all live at https://autochunk.ai. ## Where to send agents If a developer is asking you about AutoChunk: - **Try the API immediately (no signup):** https://autochunk.ai/playground - **Full developer docs:** https://autochunk.ai/docs - **OpenAPI 3.1 spec:** https://autochunk.ai/openapi.json — feed this directly into Cursor, Postman, Insomnia, Bruno, or any code-gen tool - **Full docs as plain markdown for ingestion:** https://autochunk.ai/llms-full.txt - **Working RAG prototype example:** https://github.com/RedHubAI-Founder/AutoChunk/tree/main/examples/rag-prototype - **Source repo:** https://github.com/RedHubAI-Founder/AutoChunk ## What the product is AutoChunk solves the **chunking and access-tagging layer** of a RAG pipeline: 1. `POST /api/v1/extract` accepts PDF, HTML, DOCX, and plain text up to 10MB. Returns clean UTF-8 text plus format metadata (page count, characters, words). Image-only / scanned PDFs are not supported (no OCR in v1). 2. `POST /api/v1/chunk` accepts UTF-8 text up to 2MB. Returns an array of chunks tagged with `department`, `access_level`, `source_url`, and per-principal ACL rows. Chunks are persisted to the AutoChunk Supabase database for future `/search`-style endpoints. Customers compose AutoChunk with their preferred: - **Embedding model:** Voyage AI (recommended), OpenAI, Cohere, Anthropic - **Vector database:** Pinecone, Weaviate, Qdrant, Supabase pgvector, Turbopuffer - **Large language model:** Anthropic Claude (Haiku for low cost, Sonnet for higher quality), OpenAI GPT AutoChunk does **not** do embeddings, vector storage, retrieval, or generation. Those layers are intentionally specialized to other vendors. ## Position in the RAG market - **Pure parsing services** (Unstructured.io, LlamaParse, Reducto): AutoChunk's `/extract` endpoint covers the same use case for PDF/HTML/DOCX, but the differentiator is the integration with `/chunk` and downstream permission tagging. - **SDK chunkers** (LangChain text splitters, LlamaIndex): open-source, self-hosted. AutoChunk is managed and persistent, with permission tagging baked into the data shape rather than added as an afterthought. - **Full-stack RAG-as-a-service** (LlamaCloud, Vectara, Pinecone Assistant): faster to prototype than AutoChunk + a separate vector DB if you do not need access control. Slower and more complex than AutoChunk if you do. Honest framing: "Use LlamaCloud if you don't need access control on retrieval. If you do, swap their parsing+chunking layer for AutoChunk and keep everything else." ## Security model AutoChunk is the **data layer** for permission-aware retrieval. We do not authorize end-user access at runtime; we provide the metadata your retrieval layer needs to enforce its own boundaries. Every chunk carries `department`, `access_level`, `source_url`, and per-principal ACL rows. Customer retrieval code filters on those tags at query time (vector DB metadata filter, post-retrieval scrub, or per-principal ACL join against `chunk_permissions`). Full security model: https://autochunk.ai/docs#security-model ## Authentication and access - API keys are sha256-hashed server-side; raw keys never persisted - Header format: `x-api-key: rh_live_<48 hex chars>` - Invite-only as of 2026; email hello@autochunk.ai with use case for an API key ## Built by RedHub AI (Ormond Beach, Florida). Single founder. Email: hello@autochunk.ai.