claude-code - 💡(How to fix) Fix Opus 4.7 1M via Bedrock: VSCode extension stream ends with 0 events; fallback renders as "Unhandled case: [object Object]" [1 participants]

Streaming request opens, Bedrock closes it with zero events:

[DEBUG] [API REQUEST] /model/global.anthropic.claude-opus-4-7/invoke-with-response-stream source=sdk
[DEBUG] Stream started - received first chunk
sdk_stream_ended_no_result { had_error: true, message_count: 556 }
[ERROR] Stream completed without receiving message_start event - triggering non-streaming fallback
[ERROR] Error streaming, falling back to non-streaming mode: Stream ended without receiving any events

Non-streaming fallback fires and also fails — the resulting error is passed to the UI error handler which stringifies it as [object Object].

TL;DR

The issue can be mitigated by investigating the streaming request closure with zero events and handling the error properly in the non-streaming fallback.

Guidance

• Investigate why the streaming request is closing with zero events, as indicated by the sdk_stream_ended_no_result log message, to determine if it's a server-side or client-side issue.
• Review the error handling in the non-streaming fallback to ensure it properly handles the error and provides a meaningful error message instead of stringifying it as [object Object].
• Verify that the message_count threshold of 556 is not a contributing factor to the issue, potentially by testing with a lower or higher number of turns.
• Check the Bedrock account configuration and the global.anthropic.claude-opus-4-7 model settings to ensure they are correctly set up for streaming requests.

Example

No code snippet is provided as the issue lacks specific code details, but reviewing the error handling in the non-streaming fallback might involve checking how the error is caught and handled, for example:

try {
  // non-streaming fallback code
} catch (error) {
  // properly handle the error and provide a meaningful error message
  console.error('Error in non-streaming fallback:', error);
  // display a user-friendly error message
}

Notes

The issue seems to be related to the streaming request and error handling, but without more information about the code and configuration, it's difficult to provide a more specific solution.

Recommendation

Apply workaround: Investigate and fix the streaming request closure and error handling issues, as it's unclear if upgrading to a fixed version would resolve the problem without more information.