Description

Setting imageSize to 512px throws error on google:gemini-3.1-flash-image-preview with AI Gateway. Works fine with 1K, 2K, etc.

"providerOptions": {
"google": {
"responseModalities": [
"IMAGE"
],
"imageConfig": {
"aspectRatio": "4:5",
"imageSize": "512px"
},
"thinkingConfig": {
"thinkingLevel": "high",
"includeThoughts": false
},
"safetySettings": [
{
"category": "HARM_CATEGORY_HATE_SPEECH",
"threshold": "BLOCK_LOW_AND_ABOVE"
},
{
"category": "HARM_CATEGORY_HARASSMENT",
"threshold": "BLOCK_LOW_AND_ABOVE"
},
{
"category": "HARM_CATEGORY_SEXUALLY_EXPLICIT",
"threshold": "BLOCK_LOW_AND_ABOVE"
},
{
"category": "HARM_CATEGORY_DANGEROUS_CONTENT",
"threshold": "BLOCK_LOW_AND_ABOVE"
}
]
}
},
"headers": {
"user-agent": "ai/5.0.140"
}
},
"statusCode": 400,
"responseHeaders": {
"cache-control": "public, max-age=0, must-revalidate",
"content-type": "application/json",
"date": "Fri, 27 Feb 2026 00:24:37 GMT",
"server": "Vercel",
"strict-transport-security": "max-age=63072000; includeSubDomains; preload",
"transfer-encoding": "chunked",
"vary": "rsc, next-router-state-tree, next-router-prefetch, next-router-segment-prefetch",
"x-matched-path": "/v1/ai/language-model",
"x-vercel-cache": "MISS",
"x-vercel-id": "yul1::iad1::ps6qm-1772151877048-4b033f111fba"
},
"responseBody": "{"error":{"message":"invalid google provider options","type":"AI_InvalidArgumentError","param":{"error":"invalid google provider options","statusCode":400,"name":"AI_InvalidArgumentError","message":"invalid google provider options","argument":"providerOptions","type":"AI_InvalidArgumentError"}},"providerMetadata":{"gateway":{"routing":{"originalModelId":"google/gemini-3.1-flash-image-preview","resolvedProvider":"vertex","resolvedProviderApiModelId":"gemini-3.1-flash-image-preview","internalResolvedModelId":"vertex:gemini-3.1-flash-image-preview","fallbacksAvailable":["google"],"internalReasoning":"Selected vertex as preferred provider for gemini-3.1-flash-image-preview. 1 fallback(s) available: google","canonicalSlug":"google/gemini-3.1-flash-image-preview","attempts":[{"provider":"vertex","internalModelId":"vertex:gemini-3.1-flash-image-preview","providerApiModelId":"gemini-3.1-flash-image-preview","credentialType":"system","success":false,"error":"invalid google provider options","startTime":791029.992866,"endTime":791031.199065},{"provider":"google","internalModelId":"google:gemini-3.1-flash-image-preview","providerApiModelId":"gemini-3.1-flash-image-preview","credentialType":"system","success":false,"error":"invalid google provider options","startTime":791049.776579,"endTime":791050.376022}],"modelAttemptCount":1,"modelAttempts":[{"modelId":"google/gemini-3.1-flash-image-preview","canonicalSlug":"google/gemini-3.1-flash-image-preview","success":false,"providerAttemptCount":2,"providerAttempts":[{"provider":"vertex","internalModelId":"vertex:gemini-3.1-flash-image-preview","providerApiModelId":"gemini-3.1-flash-image-preview","credentialType":"system","success":false,"error":"invalid google provider options","startTime":791029.992866,"endTime":791031.199065},{"provider":"google","internalModelId":"google:gemini-3.1-flash-image-preview","providerApiModelId":"gemini-3.1-flash-image-preview","credentialType":"system","success":false,"error":"invalid google provider options","startTime":791049.776579,"endTime":791050.376022}]}],"totalProviderAttemptCount":2}}}}",
"isRetryable": false,
"data": {
"error": {
"message": "invalid google provider options",
"type": "AI_InvalidArgumentError",
"param": {
"error": "invalid google provider options",
"statusCode": 400,
"name": "AI_InvalidArgumentError",
"message": "invalid google provider options",
"argument": "providerOptions",
"type": "AI_InvalidArgumentError"
}
},
"providerMetadata": {
"gateway": {
"routing": {
"originalModelId": "google/gemini-3.1-flash-image-preview",
"resolvedProvider": "vertex",
"resolvedProviderApiModelId": "gemini-3.1-flash-image-preview",
"internalResolvedModelId": "vertex:gemini-3.1-flash-image-preview",
"fallbacksAvailable": [
"google"
],
"internalReasoning": "Selected vertex as preferred provider for gemini-3.1-flash-image-preview. 1 fallback(s) available: google",
"canonicalSlug": "google/gemini-3.1-flash-image-preview",
"attempts": [
{
"provider": "vertex",
"internalModelId": "vertex:gemini-3.1-flash-image-preview",
"providerApiModelId": "gemini-3.1-flash-image-preview",
"credentialType": "system",
"success": false,
"error": "invalid google provider options",
"startTime": 791029.992866,
"endTime": 791031.199065
},
{
"provider": "google",
"internalModelId": "google:gemini-3.1-flash-image-preview",
"providerApiModelId": "gemini-3.1-flash-image-preview",
"credentialType": "system",
"success": false,
"error": "invalid google provider options",
"startTime": 791049.776579,
"endTime": 791050.376022
}
],
"modelAttemptCount": 1,
"modelAttempts": [
{
"modelId": "google/gemini-3.1-flash-image-preview",
"canonicalSlug": "google/gemini-3.1-flash-image-preview",
"success": false,
"providerAttemptCount": 2,
"providerAttempts": [
{
"provider": "vertex",
"internalModelId": "vertex:gemini-3.1-flash-image-preview",
"providerApiModelId": "gemini-3.1-flash-image-preview",
"credentialType": "system",
"success": false,
"error": "invalid google provider options",
"startTime": 791029.992866,
"endTime": 791031.199065
},
{
"provider": "google",
"internalModelId": "google:gemini-3.1-flash-image-preview",
"providerApiModelId": "gemini-3.1-flash-image-preview",
"credentialType": "system",
"success": false,
"error": "invalid google provider options",
"startTime": 791049.776579,
"endTime": 791050.376022
}
]
}
],
"totalProviderAttemptCount": 2
}
}
}
}
},
"statusCode": 400,
"type": "internal_server_error"
}

AI SDK Version

"@ai-sdk/gateway": "^2.0.46",
"ai": "^5.0.140",

Code of Conduct

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