Bug Smash: restoring dropped Gemini chat config in Sentry's JavaScript SDK

This is a submission for DEV's Summer Bug Smash: Clear the Lineup powered by Sentry.

Project Overview

Sentry's JavaScript SDK auto-instruments Google GenAI so every Gemini call shows up as a span in your trace, with the model, the generation config and the system instruction attached. This entry fixes a silent regression in that instrumentation: chat calls were dropping the configuration they ran with, so the trace no longer told you how the model was set up. The fix is one focused change in @sentry/server-utils. It ships with unit tests. I verified it end to end against the live Gemini API.

Bug Fix or Performance Improvement

This is a bug fix for getsentry/sentry-javascript#20086, filed by a Sentry maintainer.

Bug Smash: restoring dropped Gemini chat config in Sentry's JavaScript SDK

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