Oracle System

Overview

Every market has a pre-defined oracle type that determines how it resolves. FatTail supports three oracle types:

1. Admin Oracle

The simplest resolution method. A trusted platform operator manually resolves the market.

• Best for: Early-stage markets, custom events
• Speed: Immediate
• Trust: Centralized

2. Price Feed Oracle

Automated resolution using external price data from CoinGecko.

• Best for: Crypto price markets (BTC, ETH, etc.)
• Speed: Automatic at market expiration
• Trust: Data-driven, deterministic

How it works

1. Market has a target price and expiration date
2. At expiration, the system queries CoinGecko’s /simple/price API
3. If the actual price meets the condition, the market resolves Yes; otherwise No

3. Optimistic Oracle

A UMA-style community-driven resolution for subjective events. See Optimistic Oracle for details.

• Best for: Geopolitical, macro, subjective events
• Speed: 24-72 hours (includes challenge period)
• Trust: Decentralized, incentive-aligned

Resolution criteria

Every market with an optimistic oracle must define:

• Yes criteria: Exact conditions for a Yes resolution
• No criteria: Exact conditions for a No resolution
• Evidence rules: What sources are acceptable
• Ambiguity rules: How edge cases are handled
• Void conditions: When the market should be voided