Zovo Fair Draw
Run a prize draw on a page anyone can check, with proof of a fair pick.
Zovo Fair Draw makes a hosted page for a giveaway, a door prize, a classroom pick or a team raffle without tickets. Entrants add their name from one link, or you paste the list. From the moment it is made, the page shows a SHA-256 commitment of a secret seed and the time it was made. At the draw, the seed is revealed and the winners follow from a published algorithm, so anyone can re-run it with a short Python script and get the same names.
What it does
- A public entry page anyone opens from one link, without an account
- Commitment shown from the moment the page is made: the seed's SHA-256 hash, so anyone can check later that the seed was not swapped
- Winners from HMAC-SHA256 with rejection sampling (no modulo bias)
- Backup winners in a fixed order, in case a winner cannot take the prize
- After the draw: seed, entry list hash, each step, and a Python script to verify
- Organizer can add a list of names from chat; CSV export of entries and results
Try asking
“Run a prize draw for our team lunch voucher, 1 winner and 2 backups, people enter their own names”
“Make a fair draw with these names: Ana, Ben, Chloe, Dev, Emma, Farid — 2 winners”
“Draw the winners for my prize draw”
Limitations
- For free draws only: the organizer confirms nobody pays to enter. It does not take payments, sell tickets, or handle bets or money
- Up to 500 entries, 20 winners and 10 backup winners per draw
- One entry per name; it does not check identities
- Pages expire after 90 days
Add it
ChatGPT: once Zovo Fair Draw is approved, add it from the ChatGPT plugin directory.
Claude: go to Customize > Connectors > Add custom connector and enter
https://fair-draw.zovo.one/mcp. No sign-in is needed. Once Zovo Fair Draw is listed in the Claude connector directory, you can add it from there too.Other MCP clients can connect to the same endpoint: https://fair-draw.zovo.one/mcp