CVIN is a compute-asset identity registry for GPUs: a VIN-style identifier (manufacturer.model.form.mem:serial-hash) plus a resolution layer with hash-chained observation history and ed25519-signed official verification reports. Built for lenders, lessors and insurers of GPU fleets who need portable, verifiable device identity. Free resolve; x402-paid history and continuity proof at $0.05 per call; signed official report at $2. MCP server also available at /mcp with the same pricing.