Definition
An oracle announcement is the message an oracle publishes before an event occurs, committing in advance to sign its eventual outcome. It contains an event descriptor (what the event is and which outcomes are possible) plus one or more public nonces, also called R-values, that the oracle will later use to produce its signatures. By releasing this material ahead of time, the oracle gives contract builders everything they need to prepare a Discreet Log Contract (DLC) covering every possible result.
Why pre-committing matters
The nonce in an announcement is single-use and tied to one event. Schnorr signature math means that if an oracle ever signs two different outcomes using the same committed nonce, anyone can recover the oracle's private key from the two signatures. This turns equivocation into financial suicide for a reputable oracle, giving the system its accountability. The announcement therefore acts as a binding, public promise: "I will sign exactly one outcome of this event with this key material."
Building the contract around it
From the announcement's nonce and outcome set, the two contract parties compute the encryption points for each possible result and build a full set of pre-signed payout transactions. None of this requires the oracle's involvement or knowledge. When the event resolves, the oracle issues a separate attestation that decrypts exactly one of those transactions. An announcement with no matching attestation simply means the oracle stayed silent, and the contract's refund path eventually applies.
The announcement is the front half of the oracle workflow that ends with oracle attestation and settles through contract execution transactions.
In Simple Terms
An oracle announcement is the message an oracle publishes before an event occurs, committing in advance to sign its eventual outcome. It contains an event…