Your LLM just cited a professor who doesn't exist. CKS makes that mechanically impossible. 19 tools give AI a verifiable knowledge backbone: semantic search, type-safe ontologies, cryptographic source verification, and field-level auto-merge — all triggered by plain English in Claude Desktop. No coding, no API keys, no cloud. Just a conversation. And suddenly your AI can't bluff anymore. Open source. MIT. Install: pip install cks-mcp.