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Always-on tracing for production and preview traffic
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Vercel's always-on tracing, now in beta, continuously samples live production and preview traffic so teams can debug real user requests without reproducing them, with collection controlled by user-defined sampling rules.
This moves tracing from manual reproduction to continuous sampling of real traffic, but nothing is collected until you explicitly add a rule, so cost and coverage are entirely user-driven. Framework and custom spans require additional instrumentation with @vercel/otel, and trace retention is limited by plan tier ranging from one hour to three days.
Written by elseif from the cluster below · every claim links back to a sourceThe three things worth knowing
Always-on tracing continuously samples live production and preview traffic, unlike session tracing which only captures requests from your own browser.
Sampling rules control collection by environment and optional path prefix, priced at $0.50 per 1M span units, with no collection until a rule is added.
Infrastructure and outbound fetch spans are captured automatically, but framework and custom spans require instrumenting your app with @vercel/otel.
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