It places the order. You set what it may never do.
A strategy is a standing instruction with hard bounds. Everything inside them is automatic; nothing outside them happens, and when a trade is refused the reason is stored next to the decision.
From market to order
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Propose
The evidence engine prices every open market with enough recent flow and keeps the ones whose edge clears your floor. A market it cannot price produces no candidate at all rather than a low-confidence guess.
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Review
A model reads the question and the evidence and catches what the arithmetic misses: flow that is one account rather than a consensus, or a question that resolves on something a trade tape cannot see. It can decline or lower confidence. It cannot raise it, and it cannot name a market or a side of its own.
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Size
Quarter-Kelly on the bankroll you set, scaled by confidence, capped by your per-trade limit. Full Kelly is optimal only when the probability is exactly right, and ours is an estimate off a trade tape.
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Place
The order row is written before the network call, so a process that dies mid-flight leaves a record instead of a silent position. The venue receives our client order id as its idempotency key, so a retry cannot fill twice.
Two venues, one order model
Kalshi and Polymarket disagree about almost everything at the wire. PredictHQ speaks each one natively and hands you a single shape: a side, a limit price as a probability, and a size.
Kalshi
RSA-PSS signature per request
Prices cross the wire in whole cents, so a buy limit rounds down. Rounding up would pay more than the decision authorized, which is the one direction that must never happen.
Polymarket
API key trio plus an EIP-712 order signature
Two independent signatures. The first proves the key and only gets the request in the door; the second is made with your wallet key and is what actually authorizes moving funds.
Manual approval is the same code path
Leave a strategy on manual and decisions queue for you instead of executing. Approving one runs the identical executor, with the identical risk checks. A manual path that skips a check is a manual path that eventually places an order the schedule would have refused.
Your keys are sealed
Venue credentials are encrypted with your application key and opened only to sign a request. They are never logged, never returned by the API, and never echoed back in an error. Connecting an account verifies the keys against the venue before storing them as usable, so a mistyped key fails in a form rather than at four in the morning.
Watch it decide before you arm it
Every plan sees the decisions, with evidence. Only some of them place the order.