Bedrock Claude Sonnet 4 Fails: UnknownOperationException Bug

by Omar Yusuf 61 views

Hey guys! Let's dive into a peculiar issue we've encountered with the Bedrock Claude Sonnet 4 model. It seems we're hitting an UnknownOperationException when trying to use the /messages endpoint. This is definitely something we need to iron out, so let's break down what's happening, how to reproduce it, and what we know so far.

What's Going On?

The core problem is that when we make a request to the /messages endpoint using the bedrock/converse/us.anthropic.claude-sonnet-4-20250514-v1:0 model, we're getting an error response. This error is specifically an UnknownOperationException, which suggests that the operation we're trying to perform is not recognized or supported by the service at this time. This is quite a roadblock, especially if you're relying on this endpoint for your applications. To really dig into this, let's look at how we can reproduce the issue and the error message itself.

Reproducing the Issue

To reproduce this bug, you'll need to make a request to the /messages endpoint. Here’s a simple way to think about it:

  1. Use the model identifier: bedrock/converse/us.anthropic.claude-sonnet-4-20250514-v1:0.
  2. Send a standard message request to the /messages endpoint.
  3. Observe the response.

If you're encountering the same issue, you should see the error message detailed below. The key here is to ensure you're targeting the correct endpoint and model version. Sometimes, a simple typo or incorrect configuration can lead to these types of errors, so double-checking your request details is always a good first step. But if everything looks right and you're still seeing the error, then we know there's something deeper going on.

The Error Message

The error we're seeing is pretty explicit, which is helpful. Here’s the error response we're getting:

{
 "Output": {
 "__type": "com.amazon.coral.service#UnknownOperationException"
 },
 "Version": "1.0"
}

This JSON response tells us a few things. First, the __type field indicates that this is an UnknownOperationException from the com.amazon.coral.service. This means the error is originating from the Amazon Coral service, which is part of the AWS infrastructure. The Version field simply indicates the version of the error response format.

The crux of the issue is the UnknownOperationException. This generally means that the service doesn't recognize the operation we're trying to perform on the specified endpoint. This could be due to a number of reasons, such as:

  • The endpoint not supporting the specific operation.
  • A misconfiguration on the service side.
  • A bug in the service that's causing it to misinterpret the request.
  • An outdated or incorrect model version being used.

To really understand what's going on, we need to rule out the common culprits and dig deeper into the specifics of the service and the request we're making.

Digging Deeper: Potential Causes and Next Steps

So, what could be causing this UnknownOperationException? Let's brainstorm some potential causes and outline the next steps we can take to resolve this issue.

  1. Endpoint Misconfiguration: It's possible that the /messages endpoint for the bedrock/converse/us.anthropic.claude-sonnet-4-20250514-v1:0 model is not correctly configured. This could be an issue on the backend service side, where the endpoint isn't properly mapped to the model or the operation. To check this, we might need to reach out to the service provider or consult the documentation to ensure the endpoint and model combination are valid.

  2. Incorrect Model Version: Another possibility is that the model version we're using (20250514-v1:0) is either outdated or not supported for the /messages endpoint. Sometimes, older model versions are deprecated, or specific endpoints might only support certain versions. To verify this, we should check the official documentation or API specifications to confirm that this model version is compatible with the /messages endpoint. If it's not, we might need to update to a newer version or use a different endpoint.

  3. Service Bug: Let's face it, sometimes there are bugs in the service itself. It's possible that there's an issue in the Bedrock service that's causing it to misinterpret the request or fail to recognize the operation. If this is the case, there's not much we can do directly except report the issue and wait for the service provider to fix it. However, before jumping to this conclusion, we should exhaust other possibilities.

  4. Request Format: It’s crucial to ensure that the request we're sending is correctly formatted and includes all the necessary parameters. A malformed request can sometimes trigger an UnknownOperationException if the service can't properly parse it. We should double-check the request payload against the expected format in the API documentation. Are we including all the required fields? Are the data types correct? A small error in the request structure can sometimes lead to big problems.

  5. Authentication and Authorization: Although less likely in this specific case, it's worth considering whether there might be an issue with authentication or authorization. Do we have the necessary permissions to access the /messages endpoint and the specified model? If our credentials are not correctly configured, the service might reject the request with an UnknownOperationException as a generic error. We should verify that our API keys or access tokens are valid and have the required permissions.

Next Steps

To move forward, here’s a plan of action:

  • Consult Documentation: The first step is to dive into the official documentation for the Bedrock Claude Sonnet 4 model and the /messages endpoint. We need to verify the supported operations, model versions, and request formats. This will help us rule out any obvious misconfigurations or incorrect usage.
  • Simplify the Request: Try sending a very basic request to the /messages endpoint with the bare minimum required parameters. This can help us isolate whether the issue is related to specific request parameters or the endpoint itself. If a simple request works, we can gradually add complexity to identify the problematic part.
  • Check Model Version Compatibility: Verify that the 20250514-v1:0 model version is compatible with the /messages endpoint. If it's not, we should try using a different version or endpoint, as recommended by the documentation.
  • Examine Logs: If possible, dig into the logs on both the client and server sides. Logs can provide valuable clues about what's happening behind the scenes and help pinpoint the source of the error. Look for any error messages, warnings, or unexpected behavior that might indicate the root cause.
  • Contact Support: If we've exhausted all other options and still can't resolve the issue, it's time to reach out to the support team for the Bedrock service or the Claude Sonnet 4 model. They might have insights into known issues or be able to help us troubleshoot the problem more effectively.

By systematically investigating these potential causes, we can hopefully get to the bottom of this UnknownOperationException and get the /messages endpoint working as expected. It’s all about breaking down the problem, trying different solutions, and not being afraid to ask for help when needed.

Relevant Log Output

Unfortunately, there's no relevant log output provided in the original report. Log outputs are super helpful because they give us a peek into what's happening behind the scenes. They often contain detailed error messages, timestamps, and other contextual information that can help pinpoint the exact cause of the problem. Without log output, we're essentially working in the dark, relying solely on the error message itself and our understanding of the system. If we had logs, we might see things like:

  • Request details: The full request payload that was sent to the /messages endpoint, including headers and body.
  • Server-side errors: Any exceptions or errors that occurred on the server while processing the request.
  • Authentication information: Details about how the request was authenticated and whether there were any issues.
  • Routing information: How the request was routed within the service and whether it reached the correct destination.

In the future, including relevant log output in bug reports can significantly speed up the troubleshooting process. It gives developers a much clearer picture of what's going on and helps them identify the root cause more quickly.

Are You a ML Ops Team?

The report indicates that the person experiencing this issue is not part of an ML Ops team. This is useful context because it helps us understand the level of technical expertise and the environment in which the issue is occurring. If the person were part of an ML Ops team, we might assume they have access to more advanced debugging tools and a deeper understanding of the system. Since they're not, we need to provide more detailed and step-by-step guidance to help them troubleshoot the problem.

What LiteLLM Version Are You On?

The reporter is using LiteLLM version 1.75.5. This is important information because it tells us which version of the LiteLLM library is being used to interact with the Bedrock Claude Sonnet 4 model. Knowing the version can help us determine if the issue is related to a specific bug or compatibility problem in that version. For example, there might be known issues in version 1.75.5 that have been fixed in later versions. If that's the case, upgrading to the latest version of LiteLLM might resolve the problem. Additionally, if we can reproduce the issue on the same version, we can be more confident that it's a genuine bug and not just a configuration issue.

Twitter / LinkedIn Details

There's no Twitter or LinkedIn information provided in the report. While this isn't directly relevant to the technical issue, it can sometimes be helpful to have contact information for the reporter in case we need to follow up with them for more details or to provide updates on the fix. In a collaborative environment, being able to communicate directly with the person experiencing the issue can make the troubleshooting process much smoother and more efficient.

Final Thoughts and Next Steps

Okay, so we've dug into this UnknownOperationException with the Bedrock Claude Sonnet 4 model on the /messages endpoint. We've covered how to reproduce it, the error message itself, potential causes, and a plan of action for troubleshooting. The key takeaways are:

  • The UnknownOperationException suggests that the service doesn't recognize the operation we're trying to perform.
  • Potential causes include endpoint misconfiguration, incorrect model version, a service bug, a malformed request, or authentication issues.
  • We need to consult the documentation, simplify the request, check model version compatibility, examine logs, and potentially contact support.
  • Including relevant log output in bug reports is crucial for faster troubleshooting.

So, what's the next step? Let's start by diving into the Bedrock and Claude Sonnet 4 documentation. We need to verify that the model version and endpoint combination are valid and that we're formatting the request correctly. If everything looks good there, we can try sending a simplified request to see if that works. And if we're still stuck, we'll need to dig into the logs (if available) or reach out to support for assistance.

Remember, debugging is a process of elimination. We need to systematically rule out potential causes until we find the root of the problem. It can be frustrating, but with a methodical approach and a bit of persistence, we can usually get to the bottom of it. Let's keep each other updated on our progress and work together to resolve this issue!

Hopefully, by working through these steps, we can resolve this issue and get back to building awesome things with the Bedrock Claude Sonnet 4 model. Let's keep the conversation going and share any insights or findings as we continue to investigate.