# Function start type now available in Runtime Logs

By Steven Van · 2025-12-22

Vercel's Runtime Logs detail panel now shows whether a Function invocation was Hot, Hot (prewarmed), or Cold, with duration for cold starts.

Runtime Logs now shows the start type for every request that invokes a [Vercel](<https://creatorstoolbox.com/tools/vercel>) Function. The detail panel on the right lists the invocation as Hot, Hot (prewarmed), or Cold, and for Cold starts it also shows the duration, for example Cold (280ms).

The field appears in the Function section of the log details alongside function name, location, runtime, duration, and memory usage, making it possible to see at a glance whether a slow request was caused by a cold start. Details are in the [Runtime Logs](<https://vercel.com/docs/logs/runtime>) documentation.

![Layout to visualize the runtime logs.](<https://7nyt0uhk7sse4zvn.public.blob.vercel-storage.com/front/docs/observability/request-log-overview-light.png?lightbox>)

Layout of the Runtime Logs panel where the feature appears.

![Layout to visualize the runtime logs in live mode.](<https://7nyt0uhk7sse4zvn.public.blob.vercel-storage.com/front/docs/observability/request-live-logs-light.png?lightbox>)

Runtime Logs layout in live mode.

![Vercel](<https://www.google.com/s2/favicons?domain=vercel.com&sz=128>)

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[Original source](<https://vercel.com/docs/logs/runtime>)

[Read Function start type now available in Runtime Logs on Creators Toolbox](<https://creatorstoolbox.com/blog/vercel-function-start-type-now-available-in-runtime-logs>)

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Canonical source: https://creatorstoolbox.com/blog/vercel-function-start-type-now-available-in-runtime-logs