Anthropic SDK Raises ValueError on Bedrock Streaming SSE Error Events

What this error means

ValueError from anthropic._streaming on Bedrock SSE error events — internalServerException is a Anthropic API failure pattern reported for developers trying to fix anthropic sdk valueerror on bedrock sse internalserverexception events. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

Bedrock SSE returns error event with :exception-type: internalServerException and JSON body with message. Anthropic SDK’s _stream_decoder raises ValueError instead of handling the error event gracefully. Stack trace points to _streaming.py line 211.

Common causes

• Bedrock SSE streams sometimes produce error events with internalServerException type. Anthropic SDK raises unhandled ValueError instead of a typed exception. Affects production Bedrock users with intermittent backend errors.
• Bedrock SSE returns error event with :exception-type: internalServerException and JSON body with message. Anthropic SDK’s _stream_decoder raises ValueError instead of handling the error event gracefully. Stack trace points to _streaming.py line 211.

Quick fixes

1. Confirm the exact error signature matches ValueError from anthropic._streaming on Bedrock SSE error events — internalServerException.
2. Check the Anthropic API account, local tool state, and provider configuration involved in the failing workflow.
3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/anthropics/anthropic-sdk-python/issues/1477

Evidence note: Bedrock SSE returns error event with :exception-type: internalServerException and JSON body with message. Anthropic SDK’s _stream_decoder raises ValueError instead of handling the error event gracefully. Stack trace points to _streaming.py line 211.

Related errors

• Anthropic SDK Bedrock ValueError streaming
• Bedrock SSE internalServerException handling
• Anthropic SDK streaming error event

FAQ

What should I check first?

Start with the exact ValueError from anthropic._streaming on Bedrock SSE error events — internalServerException text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Anthropic API workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without ValueError from anthropic._streaming on Bedrock SSE error events — internalServerException.