scheduleCancel (gRPC) | Hyperliquid API Docs

Schedule automatic cancellation of all orders at a future time on Hyperliquid. Implements dead-man's switch for risk management.

Schedule automatic cancellation of all open orders at a specified future time. Acts as a dead-man's switch for trading systems, ensuring orders are cancelled if the system stops responding.

Sample Data

JSON

{
  "signature": {
    "r": "0x716e2f7591f552ba784c39fa3198c71a83fc13d93d206aa650571206149cb747",
    "s": "0x6e021299550e2b71871f3e98acf02c45c4fe5c0a09b4fc1e613db585eb9d0150",
    "v": 28
  },
  "action": {
    "type": "scheduleCancel",
    "time": 1768146928010
  },
  "nonce": 1768146913010
}

View this transaction on Hypurrscan

Field Reference

Action Fields

Field	Type	Description
`type`	string	Always `"scheduleCancel"`
`time`	number	UTC timestamp (milliseconds) when orders should be cancelled

Dead-Man's Switch Pattern

Trading systems typically:

Submit orders with scheduleCancel set to T+N seconds
Continuously extend the cancellation time while operating normally
If the system fails, orders automatically cancel at the scheduled time

This prevents orphaned orders from remaining on the book if a trading bot crashes.

Use Cases

Risk Management Monitoring

Track how traders implement fail-safes:

Python

def process_scheduleCancel_action(action):
    cancel_time = action.get('time')
    if cancel_time:
        from datetime import datetime
        cancel_dt = datetime.fromtimestamp(cancel_time / 1000)
        print(f"Orders scheduled to cancel at {cancel_dt}")

Bot Health Detection

Monitor schedule cancel extensions as a proxy for bot health.

Market Stability Analysis

Track how many orders have dead-man switches configured.

order - Submit orders
cancel - Immediate order cancellation
cancelByCloid - Cancel by client order ID

scheduleCancel - Schedule Order Cancellation