api-migration silent-failures imagen-to-gemini error-handling google-deprecation

Google kills Imagen API June 24 quietly

Gemini image generation accepts Imagen parameters silently, ignores them, returns 200 OK with wrong output — half-migrated code ships undetected.

Summary

Silent failures in API migrations cascade downstream weeks later with no error signal. Response shape, endpoint, and parameter names all differ between Imagen and Gemini; defensive parsing masks the breakage until production assets stop appearing.

Why it matters

Implementation verdict

Replaces Imagen 4.0 models entirely. Requires full rewrite: new endpoint (:generateContent vs :predict), new response path (candidates[0].content.parts[0].inlineData vs predictions[0].bytesBase64Encoded), removed batch parameter (sampleCount), moved aspect-ratio namespace, dropped safety controls (personGeneration). Not ready to swap model strings. Mask-based editing has no replacement — audit that surface before committing to migration.

Sources

1.On June 24, 2026, Google shuts down every remaining Imagen model on the Gemini API
2.the migration is not loud. Imagen and Gemini's image generation are not the same API with a different model string — they are two different request shapes, two different endpoints, and two different parameter vocabularies
3.Gemini's image endpoint will happily accept a request full of Imagen-era parameters, ignore the ones it doesn't recognize, and return 200 OK with an image. Not the image you asked for. An image.
4.Gemini's image API has no sampleCount. It generates one image per call
5.personGeneration on a migrated request is — you'll notice the pattern by now — an unrecognized key, silently dropped
6.Mask-based editing has no replacement

Dev Signal

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