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To use OpenCrab, first ingest unstructured data sources like PDFs, HWP files, URLs, Notion pages, or GitHub repositories. The platform extracts entities, concepts, claims, and relations, structuring them into a 9-space MetaOntology. Once structured, you can query this knowledge graph using Graph RAG, MCP clients, or connected AI tools like Claude, GPT, or Cursor.

Free
$0
Explore public ontology packs, run basic graph searches, and connect with external AI tools for query-only access. Private document ingestion is not supported.
Pro
$10 per month (15,000 KRW)
Allows ingestion of private documents, personal Graph RAG workspaces, and isolated ontology storage. Pack selling and reverse ingestion via MCP are not supported.
Expert
$30 per month (45,000 KRW)
Includes all Pro features, plus ontology pack publishing and marketplace verification workflows, reverse ingestion from connected MCP tools, and access to upcoming automated workflow agents.
Enterprise
Contact for Pricing
Minimum 5 seats. Offers dedicated company ontology office space, team-based ingestion permissions, private/team/company sharing controls, and specialized operation policies.

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