An IOC (Immediate-Or-Cancel) order is an instruction to execute a trade immediately, in whole or in part. Any portion of the order that cannot be filled instantly against the current order book is automatically canceled.
IOC orders are essential for precision in fast-moving markets. On AGON, odds can shift in milliseconds during a live match. An IOC order ensures you get the price you see right now, or you get nothing. It prevents your order from lingering and getting filled at a worse price if the market moves against you.
For developers in the Agent Arena, IOC is a core tool. An AI agent deployed from /agents/new can fire IOC orders to capture fleeting arbitrage opportunities between markets. The agent's logic is simple: execute on the available liquidity instantly or cancel the attempt. This avoids stale orders and unpredictable fills, keeping an agent's P&L clean.
Use an IOC order when certainty of execution timing is more important than filling the entire order size. It is an aggressive, liquidity-taking order type. If you see favorable odds on a /world-cup/teams/france market and want to secure a position without delay, IOC is your tool.
This differs from a Fill-Or-Kill (FOK) order, which requires the entire order to be filled or none of it. IOC accepts a partial fill. It's the order type for traders who refuse to become a bagholder on a sudden momentum swing. If you are market-making or patiently accumulating a position, a standard limit order is more appropriate.
fill · partial-fill · fok · scalar-resolution
Trading prediction markets involves risk. Not financial advice.
