Improper processing of a Bedrock error message causes failures. #13040

Description

I'm using an internal OpenAI-compliant gateway to reach Bedrock, to access Opus 4.5. I got the following error message asking the model to do some fairly involved code transformations.

AI_TypeValidationError: Type validation failed: Value: {"id":"4ec75945-9e25-47e0-9c6f-81f7d91a32fb","error":"Error occured during streaming: 'us.anthropic.claude-opus-4-5-20251101-v1:0-cac-cr'"}.

Error message: [{"code":"invalid_union","errors":[[{"expected":"array","code":"invalid_type","path":["choices"],"message":"Invalid input: expected array, received undefined"}],[{"expected":"object","code":"invalid_type","path":["error"],"message":"Invalid input: expected object, received string"}]],"path":[],"message":"Invalid input"}] 

As I understand it, this is probably an underlying error message returned by Bedrock, which is not being processed correctly by the Bedrock provider (demanding a JSON object, not tolerating a string under the "error" key.)

Plugins

None

OpenCode version

Locally built, pulled from GH a week ago.

Steps to reproduce

1. Configure a local gateway to point at Bedrock.
2. Specify the Opus 4.5 model.
3. Ask to do a lot of simple transformations on a lot of fairly simple classes.

I know, not terribly helpful. Best I can do.

Screenshot and/or share link

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Operating System

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Terminal

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