Layer one: sealing
The Vault turns a file into ciphertext in your browser. Without the passphrase or key, the sealed file is useless to whoever holds it: a cloud drive, a mail server, a chat app, or someone who found your USB stick. AES-256-GCM also detects tampering, so a changed file is rejected rather than shown wrong.
Sealing protects the contents. It does not hide that a file exists, roughly how large it is, or when you sent it.
Layer two: the record
Anchoring writes the sealed file's hash on Robinhood Chain with your address and the block. Grants add the addresses you allowed, with an optional end time. Anyone can read this later, and nobody, including us, can change or delete it.
A record proves that you made a statement at a time. It does not enforce it: anyone who holds the sealed file and its key can open it, whatever the chain says.
What the tools cover, and what they leave to you
They encrypt and decrypt with standard primitives that ship in every modern browser, and they read and write a small public contract. They do not store your keys, they do not recover lost passphrases, and they do not make anything anonymous: transactions on Robinhood Chain are public and tied to your address.
Practical steps
- Use a long passphrase, or a generated key with a wrapped backup kept somewhere separate from the files.
- Send the key and the file through different channels when the content matters.
- Anchor only sealed files. A hash of a readable file can confirm a guess about its contents.
- Treat a grant as a note to the world, and revoke it when it stops being true.
- Keep your recovery phrase off every website, this one included. Cypra has no reason to see it and will not request it.
For the details of the file format see the format page; the legal limits are on the risks page.
