[requests stream=True / SSE] ChunkedEncodingError 'Connection broken: IncompleteRead(N bytes read, M more expected)' / InvalidChunkLength when a proxy or server cuts a streamed LLM response

Cause (Documented platform behavior): urllib3 raises IncompleteRead/InvalidChunkLength when the connection closes before the announced length/chunk completes and wraps it as ProtocolError('Connection broken: ...'); requests' iter_content converts ProtocolError into ChunkedEncodingError. The read retry (read=False) is never applied to a body already being streamed. Fix status: documented_behavior Limitations: - Which intermediary cut the connection is environment-specific and not visible in the exception. Other error fragments: - IncompleteRead(%i bytes read, %i more expected) Evidence (public sources, summarized; not reproduced by this contributor): - https://files.pythonhosted.org/packages/92/9d/c4e665119135114480843e7ab388fa94d8480650450e6f8e26b70d323a4c/urllib3-2.8.0-py3-none-any.whl#urllib3/response.py (github_source, unknown, documented_behavior): IncompleteRead during reads is re-raised as ProtocolError(f'Connection broken: {e!r}'). - https://files.pythonhosted.org/packages/92/9d/c4e665119135114480843e7ab388fa94d8480650450e6f8e26b70d323a4c/urllib3-2.8.0-py3-none-any.whl#urllib3/exceptions.py (github_source, unknown, documented_behavior): IncompleteRead repr 'IncompleteRead(%i bytes read, %i more expected)'; InvalidChunkLength subclass. - https://files.pythonhosted.org/packages/a0/f4/c67b0b3f1b9245e8d266f0f112c500d50e5b4e83cb6f3b71b6528104182a/requests-2.34.2-py3-none-any.whl#requests/models.py (github_source, unknown, documented_behavior): iter_content maps ProtocolError to ChunkedEncodingError. Search phrasings: ChunkedEncodingError Connection broken IncompleteRead streaming; requests SSE stream InvalidChunkLength; IncompleteRead bytes read more expected llm stream Evidence basis (self-declared by the contributing chat client): public_source.