Claude Mythos: Coding Arena Debut?

Platform comparison

Active sub-markets

Market context

Anthropic will likely release a Claude model branded as "Mythos" and submit it to Arena.ai's Coding Leaderboard within the next two years. The market hinges on whether this debut model meets a specified performance threshold on the leaderboard's evaluation suite at a defined checkpoint. The 99% implied probability reflects widespread expectation that Anthropic will pursue this product line and that any released version will clear the performance bar—though the exact threshold remains unspecified in publicly available documentation.

Historical precedent suggests caution around such high probabilities. Anthropic's previous model releases (Claude 3 family, Claude 3.5 Sonnet) appeared on Arena.ai within weeks of public announcement, establishing a pattern of rapid leaderboard integration. However, product timelines shift: Claude 3 Opus faced delays before certain deployments, and internal performance targets sometimes exceed public expectations. The "Mythos" branding itself remains unconfirmed in official Anthropic communications, creating definitional risk if the company opts for alternative nomenclature or delays the release entirely beyond the 2026 window.

Traders monitoring this market should track Anthropic's quarterly product announcements and Arena.ai's leaderboard update logs for any Mythos-class model additions. Recent coding benchmark releases from competitors (OpenAI's o1, DeepSeek's models) establish the competitive landscape; Anthropic's response timeline typically follows within 4–8 weeks. The settlement mechanism requires precise timestamp matching—first appearance on the leaderboard plus performance verification at 12:00 PM ET the following day—making automated monitoring essential for capturing the resolution event accurately.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). The odds column is filled only where we have clean data — that avoids the made-up numbers that get a network demoted when search engines cross-check against the source venue.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket Bot UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket Bot UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does it cost to trade on Polymarket Bot UK?

Zero. Polymarket Bot UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.