> ## Documentation Index > Fetch the complete documentation index at: https://docs.ratiofx.com/llms.txt > Use this file to discover all available pages before exploring further. # Glossary > Key terms and definitions used across Ratio documentation | Term | Definition | | --------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Adjusted MID** | Oracle mid-rate after inventory adjustment is applied. Used as the anchor for bid/ask quote construction. | | **AML/CFT** | Anti-Money Laundering / Counter-Financing of Terrorism. Regulatory requirements that all Ratio partners must comply with. | | **Atomic settlement** | A transaction model where both sides of a swap execute in a single on-chain transaction. Either both complete or neither does — there is no partial settlement. | | **Base spread** | The minimum spread floor per corridor, covering operating costs. Varies by corridor type and transaction size tier. | | **BFT** | Byzantine Fault Tolerant. The consensus mechanism used by the Kaia blockchain, providing deterministic, immediate finality. | | **Circuit breaker** | An automated safety mechanism that adjusts or restricts trading when market conditions deteriorate. Protects LP capital and partner execution quality. | | **Corridor** | A supported currency pair for FX conversion. Each corridor (e.g., USD-IDR) connects two stablecoins and has its own oracle feeds, fee schedule, and liquidity pools. | | **Fee breakdown** | The detailed fee object returned in every firm quote response, showing fixed fees, variable fees, spread components, and total cost. | | **Firm quote** | A binding, executable price with a hard expiry timestamp and inventory reservation. Accepting a firm quote triggers the atomic swap. | | **FX Engine** | Ratio's core execution component. Constructs quotes using oracle-based pricing and executes atomic swaps on-chain. | | **Herstatt risk** | The risk in traditional FX that one counterparty delivers their currency but the other fails to deliver. Eliminated by Ratio's atomic settlement. | | **IDRX** | Indonesian Rupiah stablecoin. The regulated IDR corridor anchor on the Kaia blockchain. | | **Indicative quote** | A reference price for display or planning purposes. Carries no inventory reservation, has no expiry, and is not executable. | | **Inventory skew** | A dynamic adjustment to the mid-rate that makes the beneficial trade direction cheaper and the harmful direction more expensive, attracting flow that reduces pool imbalance. | | **Kaia** | The Layer 1 blockchain on which Ratio is built. Provides sub-second BFT finality and full EVM compatibility. | | **kToken** | A rebasing receipt token issued to LPs (e.g., kUSD, kIDR). Represents the LP's pool share and automatically accrues swap fee revenue. | | **KYB** | Know Your Business. The due diligence process applied to all partners during onboarding. | | **Liquidity Hub** | The SOL component that manages stablecoin pools, coordinates rebalancing, and ensures swap availability. | | **Liquidity pool** | A single-sided, per-currency pool of stablecoins that provides depth for FX execution. Each supported stablecoin has its own dedicated pool. | | **Liquidity Provider (LP)** | An entity that deposits stablecoins into Ratio's pools and earns a share of swap fees proportional to their deposit. | | **MAS** | Monetary Authority of Singapore. The financial regulator for Singapore-related corridors. | | **MYRC** | Malaysian Ringgit stablecoin. Serves both USD-MYR and MYR-IDR corridors. | | **Off-Ramp** | The SOL component that converts stablecoins to local fiat via domestic payment rails. | | **On-Ramp** | The SOL component that converts fiat to stablecoins for entry into the SOL. | | **Oracle** | An external price feed that provides real-time FX rates. Ratio uses Pyth Network as its primary source, updated approximately every 400 milliseconds. | | **Partner** | A business entity integrated with Ratio's API — PSP, bank, stablecoin issuer, exchange, LP, or similar. | | **Pyth Network** | Ratio's primary oracle source, providing institutional-grade FX data. | | **Rebalancing** | The process of restoring pool health when FX flows create inventory imbalances. Coordinated automatically via external market makers. | | **SOL** | Stablecoin Orchestration Layer. Ratio's complete middleware stack: On-Ramp, FX Engine, Liquidity Hub, Yield Engine, Off-Ramp, and Communication Layer. | | **Spread** | The difference between bid and ask prices. Constructed dynamically from base, volatility, liquidity, and inventory components. | | **tnSGD** | Singapore Dollar stablecoin for the USD-SGD corridor. | | **USDT** | Tether's US Dollar stablecoin. The global reference stablecoin and the USD-side anchor for Ratio's corridors. | | **Webhook** | An HTTP callback sent by Ratio to your server when an event occurs — such as settlement confirmed, quote expired, or state change. | | **Yield Engine** | The SOL component that deploys idle stablecoin balances into yield strategies, maximising LP returns on surplus liquidity. |