Bedrock converseStream returns citation chunks with empty "location": { "web": {} } instead of proper document locations

I’m seeing an issue with Amazon Bedrock Converse Stream (converseStream / ConverseStreamCommand) where citations returned in streaming mode do not contain the correct document location information.

When calling Bedrock with enabled citations, input including documents, using boto3 converse_stream or JS SDK ConverseStreamCommand, the streamed output contains citation chunks shaped like:

{
  "citation": {
    "title": "My Document",
    "sourceContent": [{ "text": "..." }],
    "location": { "web": {} }
  }
}

However, based on the API documentation and on previous SDK versions, the location field should contain actual document locations, such as:

"location": {
  "documentChar": {
    "documentIndex": 0,
    "start": 0,
    "end": 50
  }
}

or

"location": {
  "documentPage": {
    "documentIndex": 0,
    "pageNumber": 1
  }
}

converseStream should return citations with correct document location metadata (documentChar, documentPage, or documentChunk) for uploaded documents, exactly as the non-streaming converse API does.

All streamed citation chunks contain location: { "web": {} }. This happens regardless of which model is used. The issue occurs in both JS and Python SDKs, which implies the issue may be on the service side rather than the SDK.

Sample python code to reproduce:

import json
import boto3

br = boto3.client("bedrock-runtime", region_name="eu-central-1")

def main():
    with open("sample.txt", "r", encoding="utf-8") as f:
        doc_text = f.read()

    payload = {
        "modelId": "eu.anthropic.claude-sonnet-4-20250514-v1:0",
        "messages": [
            {
                "role": "user",
                "content": [
                    {
                        "document": {
                            "name": "Example Document",
                            "format": "txt",
                            "source": {"text": doc_text},
                            "citations": {"enabled": True},
                        }
                    },
                    {"text": "what is this document about?"},
                ],
            }
        ],
    }

    response = br.converse_stream(**payload)

    stream = response.get("stream")
    for event in stream:
        print("=== event ===")
        print(json.dumps(event, indent=2))


if __name__ == "__main__":
    main()

We receive:

{
  "contentBlockDelta": {
    "delta": {
      "citation": {
        "title": "Example Document",
        "sourceContent": [
          {
            "text": "This is an example document content used for testing document upload functionality in the chat application."
          }
        ],
        "location": {
          "web": {} # instead of documentChar: { ... }
         }
      }
    },
    "contentBlockIndex": 1
  }
}

I already raised an issue with AWS Support, however haven't heard back yet.