This seems to be also happening with the other models aswell.

In other models, it occurs after several exchanges, but in nova, it occurs from the beginning to the end.

This occurs on all nova series.

Please provide cloudwatch logs for websocket handler.

Please provide cloudwatch logs for websocket handler.

Please let me know if this is sufficient information

I believe the Bedrock API is reporting that a guardContent field is empty for one of the ContentBlock objects. When handling a user message and applying guardrails with grounding_source, the code returns a list with {"guardContent": grounding_source} as the first item. If the grounding_source is missing or does not contain the required text fields, Bedrock rejects the request.

if (
    role == "user"
    and guardrail
    and guardrail.grounding_threshold > 0
    and grounding_source
):
    return [
        {"guardContent": grounding_source},
        {
            "guardContent": {
                "text": {"text": c.body, "qualifiers": ["query"]}
            }
        },
    ]

If grounding_source is empty or does not contain a text field, the first element in this returned list will have empty guard content.

EDIT: My Cloudwatch logs show a completely different issue vs. the one from the OP. I've made a new ticket to keep things better organized: #637

Provides cloudwatch logs for websocket handlers.

We're currently inspecting this. It seems to be happening when the tool config input scheme has the "title" key.

Please let me know if you can fix the error by deleting this key when Nova is selected.

We're working on testing more thoroughly now. We've had success by deleting the title key in the toolConfig.

'toolConfig': {
    'tools': [
        {
            'toolSpec': {
                'name': 'internet_search',
                'description': 'Search the internet for information.',
                'inputSchema': {
                    'json': {
                        'properties': {
                            'query': {
                                'description': 'The query to search for on the internet.',
                                'title': 'Query',
                                'type': 'string'
                            },
                            'country': {
                                'description': 'The country code you wish for search. Must be one of: jp-jp (Japan), kr-kr (Korea), cn-zh (China), fr-fr (France), de-de (Germany), es-es (Spain), it-it (Italy), us-en (United States)',
                                'title': 'Country',
                                'type': 'string'
                            },
                            'time_limit': {
                                'description': "The time limit for the search. Options are 'd' (day), 'w' (week), 'm' (month), 'y' (year).",
                                 'title': 'Time Limit',
                                 'type': 'string'
                            }
                        },
                       'required': ['query', 'country', 'time_limit'],
                       'title': 'InternetSearchInput', # This KEY
                       'type': 'object'
                   }
               }
           }
       }
   ]
}

@lopez-hector Thank you for your detailed investigation. As you mentioned, official doc says that no need to add title to the request. We'll fix this bug (cannot tell the ETA) but it'd be nice if you could create a PR. Thank you for your understanding.

We're currently inspecting this. It seems to be happening when the tool config input scheme has the "title" key.

Please let me know if you can fix the error by deleting this key when Nova is selected.

We're working on testing more thoroughly now. We've had success by deleting the title key in the toolConfig.

'toolConfig': {
    'tools': [
        {
            'toolSpec': {
                'name': 'internet_search',
                'description': 'Search the internet for information.',
                'inputSchema': {
                    'json': {
                        'properties': {
                            'query': {
                                'description': 'The query to search for on the internet.',
                                'title': 'Query',
                                'type': 'string'
                            },
                            'country': {
                                'description': 'The country code you wish for search. Must be one of: jp-jp (Japan), kr-kr (Korea), cn-zh (China), fr-fr (France), de-de (Germany), es-es (Spain), it-it (Italy), us-en (United States)',
                                'title': 'Country',
                                'type': 'string'
                            },
                            'time_limit': {
                                'description': "The time limit for the search. Options are 'd' (day), 'w' (week), 'm' (month), 'y' (year).",
                                 'title': 'Time Limit',
                                 'type': 'string'
                            }
                        },
                       'required': ['query', 'country', 'time_limit'],
                       'title': 'InternetSearchInput', # This KEY
                       'type': 'object'
                   }
               }
           }
       }
   ]
}

As far as I am aware the issue seems to stem from the _generate_input_schema method (in agent_tool.py) . If possible, could you explain how you're removing the title key from the JSON?