Editorial note: This guide is educational and does not provide financial, legal, or investment advice. API features, access, and rules can change; verify current official documentation before implementation.
Model events, markets, contracts, and outcomes separately
A Prediction Markets Trader API often represents several related objects. An event is the broader subject, such as an election, economic release, or sports competition. A market expresses a specific question. A contract or token represents a tradable outcome. The exact terminology varies, so an integration should map provider objects into an internal model rather than assuming names are interchangeable.
Store immutable provider identifiers alongside human-readable titles. Titles can change for clarity, while identifiers should remain stable. Preserve category, open and close times, eligible outcomes, tick size, minimum order quantity, status, rules, and links or hashes that identify the governing resolution terms.
Multi-outcome and mutually exclusive markets require additional care. A binary yes/no assumption can produce incorrect exposure calculations when the provider represents many candidates, ranges, or conditional outcomes.
Treat market price as a trading value, not certainty
Prediction-market prices are frequently interpreted as probabilities, but an application should preserve the raw market representation and explain assumptions. Prices can be affected by spread, fees, liquidity, participant constraints, market structure, and time remaining. A displayed value is not a guaranteed forecast.
Distinguish best bid, best ask, last trade, midpoint, and calculated probability. They answer different questions. A thin market may have a wide spread, making the midpoint appear precise even when executable prices are far apart. Show timestamp and liquidity context wherever a probability-like value is displayed.
When aggregating markets across providers, normalize numeric scales carefully. One interface may use decimal prices, another integer cents, and another outcome token quantities. Avoid floating-point assumptions in settlement-sensitive calculations; use exact decimal handling.
Represent the order book and trades explicitly
For order-book markets, store side, price, quantity, sequence, and timestamp. Determine whether quantities are contracts, currency units, or another measure. Clarify whether the feed is a full snapshot, incremental update, top-of-book quote, or aggregated depth.
Streaming consumers need a recovery process. Begin from a documented snapshot, apply updates in order, detect sequence gaps, and rebuild when state is uncertain. Do not continue calculating liquidity from a book that may be incomplete.
Trades should include a stable identifier when available and enough information to prevent duplicates. A chart may use trade time, while an audit pipeline may also store provider receipt time. Late or corrected events should be handled deliberately rather than silently appended.
Design for the complete market lifecycle
A market can be announced, scheduled, open, paused, closed, under review, resolved, disputed, voided, or settled. The available states and transitions vary. Avoid reducing them to open and closed. An application should preserve provider status and map it to a smaller internal state only when the mapping is explicit.
Resolution rules are central data, not legal boilerplate. Store the source, measurement method, cutoff time, treatment of delays or cancellations, and any clarification notices. A title alone may not define what causes an outcome to settle.
Settlement data should identify the final outcome, resolution timestamp, status, and any payout or void mechanics exposed by the API. Historical analytics must distinguish a resolved market from a market that was canceled or deemed invalid.
Build discovery around structured filters
Users and agents need to find relevant markets without relying on fragile title matching. Index categories, entities, dates, tags, status, liquidity measures, and provider identifiers. Normalize entity names but retain the original text.
Search results should make near-duplicate questions visible. Two markets may appear similar while using different deadlines, sources, thresholds, or geographic scopes. Display concise rule summaries and close times beside prices.
For AI-assisted research, retrieval should return the exact market rules and current state as separate fields. A model should not infer contract terms from a headline.
Track positions, orders, and exposure by outcome
A portfolio model should connect orders, fills, positions, cost basis, and settlement to the underlying market and outcome. Account for partially filled orders, open orders, fees, and positions that offset or overlap. Multi-market events can create correlated exposure even when each position is individually small.
Order validation should confirm market status, price increments, quantity increments, balance, permissions, and expiry. Use a stable client-order identifier and reconcile uncertain submissions before retrying. Apply risk limits in notional and worst-case payout terms appropriate to the platform.
Do not treat a prediction market as a guaranteed information source. Trading and prediction markets involve risk, and access or legality can depend on jurisdiction and platform rules.
Create a reproducible historical dataset
Historical research benefits from snapshots of metadata, rules, state transitions, order books, trades, and settlement. Saving only final prices removes the context needed to explain market behavior. Version rule changes and title edits.
Normalize timestamps to UTC while retaining original timezone context for deadlines. Record ingestion time and provider sequence data. Document gaps, outages, and backfills so analyses do not assume a perfect feed.
When deriving probability series, state whether the value is last trade, midpoint, volume-weighted measure, or another calculation. Reproducibility is more valuable than false precision.
Prediction Markets Trader API checklist
Before production, verify object relationships, numeric units, price increments, market states, rule access, streaming recovery, order lifecycle, account permissions, settlement behavior, regional restrictions, and data-use rights. Test paused, voided, disputed, and low-liquidity cases—not only active popular markets.
A reliable prediction-market integration preserves the contract’s rules and lifecycle with the same care it gives the price.
That foundation supports dashboards, alerts, research tools, and supervised trading workflows without presenting market prices as certainty.
Use the Trader API directory, review our API review methodology, or contact the editorial team at [email protected].