// GLOSSARY

Unified market ID

One identifier for one real-world question across venues — mapping a Kalshi ticker and a Polymarket condition ID to a single mkt_ ID. The prerequisite for cross-venue routing, price comparison, and arbitrage without hand-maintained lookup tables.

Kalshi names markets with human-readable tickers; Polymarket names them with 0x hashes and slugs. When both list "will X happen by Y date," nothing in either API tells you they're the same question. A unified market ID is the abstraction that does.

Why the mapping is genuinely hard

• Criteria drift: two markets on "the same" event can differ in resolution source, cutoff time, or threshold — a 3.0% CPI market and a "3.0% or higher" market are different instruments.
• Structure mismatch: one venue's single multi-outcome event may be another's family of binaries.
• Churn: new markets list daily; mappings rot without maintenance.

Get it wrong and "arbitrage" becomes two uncorrelated positions — the classic failure covered in Kalshi–Polymarket arbitrage.

In practice

Mithril exposes unified mkt_ IDs so one identifier addresses both venues' listings where a verified equivalence exists, which is what makes smart order routing expressible at all: you ask for the market, the router picks the venue. Design details in unified market IDs.