Two things we say, and how you check them yourself, in your own browser.
Quanta’s servers sign the replies they write, with the time each one finished. Paste the link to a shared conversation and this page checks every signature right here. Have a screenshot? Ask for the link.
A signed reply is word for word what the named Quanta model wrote, when it says. Each signature also covers the question it answered and the reply before it, so a reply put under a different question, or a conversation with turns cut out, says so.
Memory, settings, attached files and search results are not part of a receipt. A reply written on the person’s own device never reached our servers, so it has no signature; neither do replies from before October 19, 2026.
The signatures are Ed25519. This is Quanta’s public key, the only one that can make them match:
“Sealed” is a claim. Below is the SHA-256 of the weight manifest and the model library we serve, published here when the seal was made, and hashed again in your browser when you press a button.
A matching hash proves the manifest you would download is the one we published — and the manifest carries a checksum for every weight shard, so a shard that changed would fail to match its own entry.