Core concepts
Prediction market
A market where the traded asset is a share in a possible future outcome. The share pays 0 if it resolves false. Example: a “Yes” share on “Will the Fed cut rates in March?” pays $1 if the cut happens.Event, Market, Outcome
PMXT’s catalog is three levels deep. An Event is a real-world question (“2024 US Presidential Election”). A Market is a specific tradable framing of that event (“Will Trump win the 2024 election?”). An Outcome is a single side of the market (“Yes” or “No”). One event can have many markets; one market always has two or more outcomes. See Unified schema for the schema-level detail.Price as probability
Outcome prices are in the closed interval [0, 1] and are read as the market’s implied probability that the outcome resolves true. A “Yes” share trading at 0.31 pays $1 if Yes resolves true, so the market is implying a roughly 31% chance. The “Yes” price plus the “No” price for a binary market sum to approximately 1 (minus venue spread).Catalog UUID vs venue ID
PMXT assigns its own stable UUID to every market and outcome. The underlying venue (Polymarket, Kalshi, etc.) also has its own native ID — a hex condition ID, a ticker, a hash. Hosted trading requires the catalog UUID. Per-venue read endpoints return venue-native IDs. See Catalog UUID vs Venue ID for which surfaces use which.Crypto / EVM terms (for the non-crypto reader)
Wallet
An on-chain account, identified by a public address (e.g.0xAbc...). It can hold tokens and sign transactions. A wallet is controlled by a private key.
EVM private key
A 32-byte secret that controls a wallet address on any Ethereum-compatible (EVM) chain. The same key works across Ethereum, Polygon, BSC, Arbitrum, and other EVM chains — the address derives from the key, not the chain. PMXT only uses your private key for local signing; it never leaves your machine.Polygon
A specific EVM-compatible chain (chainId 137). PMXT’sPreFundedEscrow contract and Polymarket’s CLOB exchange both live on Polygon. This is the only chain you fund.
USDC
A US-dollar-pegged stablecoin (1 USDC ≈ $1) issued on many chains. PMXT uses the Polygon-native USDC for hosted trading. Bridged versions on other chains are not interchangeable.EIP-712
The typed-data signing standard PMXT uses for hosted writes. Instead of signing an opaque hex blob, your wallet signs a structured payload with named fields — making the signature human-auditable and replay-resistant. Every hosted order, cancel, and escrow action is an EIP-712 signature. See Signing.PreFundedEscrow
The non-custodial smart contract on Polygon that holds USDC for hosted trading. You deposit USDC once; subsequent trades spend from the escrow balance until you withdraw. Funds can only move against an EIP-712 signature from your wallet, so your wallet retains beneficial ownership the entire time. See Hosted Trading and Escrow Lifecycle.Trading terms
CLOB
Central Limit Order Book. The matching-engine model where bids and asks are stored in a sorted book and orders match against the best available price. Most prediction-market venues (Polymarket, Kalshi) run a CLOB.Market order
An order that executes immediately at the best available price, walking the book until filled. You specify size, not price. Set a generousslippage_pct to bound the worst price you’ll accept.
Limit order
An order that rests on the book at a specified price and only executes when a counterparty crosses it. You specify both price and size.Group A methods
In PMXT, Group A refers to the venue-agnostic trading and read methods that work identically across every hosted venue —create_order, fetch_balance, fetch_positions, fetch_my_trades, and friends. The unified surface that makes PMXT a single SDK across venues. See API Reference.
Hosted vs self-hosted
Hosted (default)
PMXT operates the catalog, the escrow contract, and the venue-submit path. You hold apmxt_api_key and a wallet private key; PMXT does everything else. See Hosted Trading.
Self-hosted
You runpmxt-core on your own machine, supply raw venue credentials, and the SDK talks directly to the venues. No API key, no escrow, no PMXT in the trade path. See Hosted vs Self-hosted for the comparison.