Creating Markets

How to create binary markets and market groups on your venue — parameters, best practices, and on-chain mechanics.

Markets are created within a venue. You need your venue ID and USDC for the creation fee.

Creating a Binary Market

A binary market is a single YES/NO question. It goes live immediately on creation.

const tx = await client.market.createMarket({
  venueId: 1n,
  question: {
    title: 'Will BTC reach $100k by end of 2026?',
    description: 'Resolves YES if Bitcoin reaches $100,000 USD on any major exchange before January 1, 2027.',
  },
  outcomes: ['Yes', 'No'],
  tickSize: parseEther('0.01'),       // $0.01 price increments
  collateralToken: USDC_ADDRESS,
  additionalReward: 0n,              // no extra UMA reward
  liveness: 0n,                      // defaults to 2 hours
});

What happens on-chain:

Validates parameters and access control
Allocates a market ID (auto-incrementing from 1)
Enriches the question data with market metadata
Generates a deterministic questionId and conditionId
Prepares the CTF condition and computes YES/NO position IDs
Collects the market creation fee (50/50 protocol/venue split)
Emits MarketCreated

Creating a Market Group

Market groups contain N mutually exclusive outcomes. The lifecycle is: create → add outcomes → activate.

// 1. Create the group
await client.market.createMarketGroup({
  venueId: 1n,
  question: 'Who will win the championship?',
  description: 'Resolves YES for the winning team.',
  collateralToken: USDC_ADDRESS,
  tickSize: parseEther('0.01'),
  additionalReward: 0n,
  liveness: 0n,
});

// 2. Add outcomes (each becomes a binary YES/NO market)
await client.market.addMarketToGroup({
  marketGroupId: 1n,
  marketName: 'Team A',
  marketQuestion: 'Will Team A win?',
});

await client.market.addMarketToGroup({
  marketGroupId: 1n,
  marketName: 'Team B',
  marketQuestion: 'Will Team B win?',
});

// 3. Optionally add placeholder slots for late additions
await client.market.addPlaceholderMarkets({
  marketGroupId: 1n,
  count: 3n,
});

// 4. Activate (locks totalMarkets, enables trading)
await client.market.activateMarketGroup({ marketGroupId: 1n });

Placeholders can be activated later with real names and questions:

await client.market.activatePlaceholder({
  marketGroupId: 1n,
  marketId: 5n,
  marketName: 'Team C',
  marketQuestion: 'Will Team C win?',
});

Writing Good Resolution Criteria

The description field is what UMA asserters and disputors use to determine the outcome. Be specific:

State the exact condition for YES vs NO
Include data sources (e.g., "any major exchange", "official results")
Include deadlines with timezone if applicable
Avoid ambiguous language

Market Parameters

Parameter	Description	Constraints
`venueId`	Which venue to create in	Must exist and be active
`question.title`	The market question	Non-empty
`question.description`	Resolution criteria	Used by UMA for disputes
`outcomes`	Outcome labels	Must be `['Yes', 'No']` for binary
`tickSize`	Price increment	Must be > 0. Common: `parseEther('0.01')`
`collateralToken`	Trading collateral	Must be UMA-whitelisted ERC-20
`additionalReward`	Extra UMA asserter reward	Added to venue default. 0 is common
`liveness`	UMA challenge period	Minimum 7200s (2 hours), values below are floored
Market creation fee	Charged to creator	Minimum 5 USDC, set per venue, 50/50 split

On-Chain Mechanics

The creation fee is pulled from your wallet via transferFrom — approve USDC to the Diamond before creating.

For market groups:

Only the group creator can add markets and activate
Maximum 50 markets per group (including placeholders)
Minimum 2 markets required to activate
totalMarkets is locked at activation — used for NegRisk conversion math
Placeholders reserve position IDs at creation; only the question text changes on activation

Creating a Price Market (Pyth)

Price markets use the priceMarket module and resolve automatically from a Pyth feed at closeTime:

const tx = await client.priceMarket.createPyth({
  venueId: 1n,
  pythFeedId: '0xe62df6c8b4a85fe1a67db44dc12de5db330f7ac66b72dc658afedf0f4a415b43', // BTC/USD
  closeTime: BigInt(Math.floor(Date.now() / 1000) + 86400), // +24h
  tickSize: parseEther('0.01'),
  collateralToken: USDC_ADDRESS,
  question: {
    title: 'Will BTC close above its open price in 24h?',
    description: 'Resolves from Pyth BTC/USD at the close timestamp.',
  },
  // strikePrice: 0n,          // omit for Up/Down; set for Strike mode
  // resolutionWindow: 3600n,  // optional window allowed after closeTime
  // tags: ['crypto', 'btc'],
});

After closeTime + resolutionWindow, anyone calls client.priceMarket.resolvePyth(marketId) — no UMA bond or assertion required. See Price Markets for the full details.

Markets support optional tags (up to 5 per market) and a metadata URI (typically IPFS) for images, extended descriptions, or structured fields consumed by the frontend. These are event-only — they are not stored on-chain, but they're indexed by the subgraph:

await client.market.updateMarketTags({ marketId: 1n, tags: ['sports', 'nba'] });
await client.market.updateMarketMetadata({ marketId: 1n, metadataURI: 'ipfs://…' });

// Equivalent methods exist for market groups:
await client.market.updateMarketGroupTags({ marketGroupId: 1n, tags: ['elections'] });
await client.market.updateMarketGroupMetadata({ marketGroupId: 1n, metadataURI: 'ipfs://…' });

Only the market creator (or venue operator) can update these.

What's Next

Resolution → — how markets reach a final outcome
Market Types → — binary, groups, and price markets
Price Markets → — Pyth integration details
Oracle Settings → — configure bond, reward, and liveness