A data source is only useful when the contract names it

A familiar dashboard shows the number you expected. That does not mean it is the number the contract will use.

A source becomes useful for a market only when the contract makes its identity and timing clear.

Trace the source chain

Write down the named publisher, document or feed, release time, revision policy, and cutoff. Keep the exact link or identifier beside the estimate.

A live data page, a later revised report, and an archived release can all describe the same event while producing different settlement evidence.

Separate observation from settlement

Use outside data to form a view, then ask whether the designated source will publish the fact in the required format. A good estimate can still be irrelevant if the contract resolves elsewhere.

If a source is delayed or unavailable, record what the rules say happens next. Do not silently substitute a more convenient feed.

Keep the version visible

When a number changes, save the old value, timestamp, and document version before updating the note. That makes revisions auditable and keeps a new observation from rewriting the original reasoning.

The useful question is not whether the source is famous. It is whether the contract points to the same source, version, and cutoff that your analysis used.

Further reading: Prices and order books · Resolution rules · Current fees.

Explore the markets: Open Polymarket (referral link).