Optimistic Oracle
This feature is currently under development. Content may be incomplete or subject to change.
An optimistic oracle is a decentralized mechanism in blockchain and Web3 systems that enables rapid inclusion of off-chain data or computation results on-chain without immediate verification. It operates on the principle of "optimistic" trust, assuming submitted data is correct unless challenged within a specified timeframe. If unchallenged, the data is considered valid; if disputed, it undergoes a verification process.
This approach significantly reduces the latency and cost associated with bringing external information on-chain, as it only requires full verification in cases of disagreement.
Optimistic oracles are particularly useful for complex computations, large datasets, or frequently updated information, enabling more efficient and scalable blockchain applications while maintaining a high degree of trust and security.
Pragma's Optimistic Oracle
You can find Pragma's first implementation of the Optimistic Oracle on Starknet here, following UMA's general interface.
Our Optimistic Oracle works by making a truth claim about the world, stating that something has happened or is true. Once asserted, the assertion enters a challenge period during which someone can dispute it. If no one disputes it during the challenge window, the statement is taken as true. In case of a dispute, the data verification mechanism intervenes.
The first iteration of the optimistic oracle is deployed on the following addresses:
| Network | Address | Explorer |
|---|---|---|
| Starknet Sepolia | 0x44ac84b04789b0a2afcdd2eb914f0f9b767a77a95a019ebaadc28d6cacbaeeb | Starkscan Voyager |
General Process
Step 1: Assertion Submission
An Asserter submits a bonded assertion about a real-world state. This assertion includes:
- Identifier: The specific price identifier being asserted
- Timestamp: When the asserted fact occurred
- Claim: Additional contextual information about the assertion
- Currency: The ERC20 token used for rewards and fees (must be DVM-approved)
- Bond: The stake amount backing the assertion's accuracy
Step 2: Dispute Window
A predefined "liveness period" begins, during which Disputers can challenge the assertion.
Disputers may use their own off-chain price feeds and methodologies to verify the assertion. If no disputes occur within this period, the assertion is presumed correct.
Step 3: Dispute Resolution
If disputed:
The assertion is forwarded to the Data Verification Mechanism for arbitration.
If undisputed:
The assertion is treated as valid after the liveness period ends.