htx-exchange HTX Mark Price, Premium Index & Basis
Focused skill for mark price, premium index, and basis kline series on HTX USDT-M perpetuals. Mark price drives liquidation; premium index drives funding rate; basis = mark − index price (the spread vs spot reference). All public.
When to use this skill
Load this skill when the user asks about:
- "BTC mark price kline 4h"
- "Show me premium index for ETH-USDT"
- "Why is the mark price different from last trade?"
- "Premium index history before this funding settlement"
- "Mark price vs index price spread on SOL"
- "Is the perpetual trading at premium or discount?"
- "BTC basis history"
Underlying tool
Drives htx-cli. Binary on $PATH or $HTX_CLI_BIN. Always pass --json.
Endpoint catalog (2)
| # | Method | Endpoint | CLI invocation | Description |
|---|---|---|---|---|
| 1 | GET | /linear-swap-ex/market/history/mark_price_kline |
htx-cli futures call GET /linear-swap-ex/market/history/mark_price_kline --query contract_code=<code>&period=<period>&size=<N> --json |
Mark price kline (used for liquidation, position PnL) |
| 2 | GET | /linear-swap-ex/market/history/premium_index_kline |
htx-cli futures call GET /linear-swap-ex/market/history/premium_index_kline --query contract_code=<code>&period=<period>&size=<N> --json |
Premium index kline (deviation of perpetual from spot, drives funding) |
Period values
1min,5min,15min,30min,60min,4hour,1day
size range: 1–2000 (typical: 200).
Contract code format
USDT-M perpetual codes follow <BASE>-USDT (e.g. BTC-USDT).
Concept reference
| Term | Definition |
|---|---|
| Mark price | Fair-value reference price = index price × (1 + premium index over a moving window). Used for liquidation triggers and unrealized PnL, NOT for matching trades. |
| Index price | Spot-based reference, weighted basket of major spot exchanges. |
| Premium index | (Mark - Index) / Index. Positive = perpetual trading at premium (longs heavy); negative = discount. |
| Funding rate | Calculated from a smoothed premium index + interest rate component. Reset every 8h. |
Typical queries → CLI
| User question | CLI command |
|---|---|
| "BTC mark 1h kline last 200 bars" | htx-cli futures call GET /linear-swap-ex/market/history/mark_price_kline --query contract_code=BTC-USDT&period=60min&size=200 --json |
| "ETH premium 15m kline" | htx-cli futures call GET /linear-swap-ex/market/history/premium_index_kline --query contract_code=ETH-USDT&period=15min&size=200 --json |
| "Is SOL trading at premium right now?" | Pull premium kline size=1 → check sign and magnitude |
| "BTC basis 1h kline last 100" | htx-cli futures call GET /index/market/history/linear_swap_basis -p contract_code=BTC-USDT -p period=60min -p basis_price_type=close -p size=100 --json |
Output guidance
Return:
- Latest mark/premium values
- 1h / 4h / 24h change
- For premium index: label as
discount (>−0.05%),neutral (±0.05%),mild premium (0.05%-0.2%),heavy premium (>0.2%)
Related skills
https://github.com/htx-exchange/htx-skills-hub/funding-rate— premium drives funding directionhttps://github.com/htx-exchange/htx-skills-hub/futures-market— index price endpoint (basis denominator)https://github.com/htx-exchange/htx-skills-hub/derivatives-analyst— (planned Layer 2) combines mark/premium/funding/OI into pressure score