Starter
/month
Monthly
- 12,000 credits/year
- Unlimited queries
- 1 month free trial
- In-app & email support
Captain is an API-first RAG platform that lets teams search large collections of unstructured documents — PDFs, S3 files, spreadsheets, scanned images — in plain English with just two API calls. Part of YC W2026, the company was founded by Lewis Polansky (CEO) and Edgar Babajanyan (CTO), who brings 4 years of experience scaling high-performance RAG pipelines.
The platform handles the entire ingestion pipeline automatically: OCR via Gemini 3 Pro, complex document parsing via Reducto, chunking, and embedding generation using Voyage AI contextualized embeddings. It employs hybrid retrieval combining dense embeddings with full-text search via reciprocal rank fusion, then re-ranks with Voyage rerank-2.5. Captain tops the Open-RAG-Benchmark with over 20% higher accuracy than standard RAG pipelines.
Captain integrates with 1,000+ data sources including S3, SharePoint, Google Drive, Confluence, Slack, and Notion. It includes role-based governance with granular metadata-based access control and is SOC 2 Type II certified. The platform provides managed vector storage, so teams don't need an external vector database.
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/month
Monthly
,600/month
Monthly
Custom
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Teams building AI agents that need accurate knowledge access
Captain powers the retrieval layer in RAG applications, while Respan monitors the LLM calls that consume retrieved results. Together they provide end-to-end observability from document retrieval through final LLM response.
Top companies in RAG Frameworks you can use instead of Captain.
RAGFlow
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Ingests 65+ file formats: PDFs, DOCX, PPTX, HTML, images, emails
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Vectara
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Docling
Converts PDFs, DOCX, PPTX, HTML, images to structured JSON/markdown
Chunkr
WhyHow
Compresr
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Side-by-side comparisons with other tools in this category.
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Last verified: March 27, 2026