What a CID means
CID stands for Content Identifier. It is the address format IPFS uses to identify data by cryptographic content, codec, and multibase information.
When you submit a CID to HiDHT, the first step is format validation. This confirms that the value is a usable IPFS identifier before any provider lookup or gateway probe runs.
Why CIDs can still be unavailable
A valid CID does not guarantee that content is currently retrievable. The content still needs reachable providers, fresh routing records, and at least one path that can serve blocks within a gateway timeout.
This is why HiDHT separates CID validation from provider discovery and gateway availability.