litellm - 💡(How to fix) Fix [Bug]: Header value must be str or bytes, not float [1 pull requests]

2026-05-08T12:21:49.200718182+02:00 stderr F ^[[92m10:21:49 - LiteLLM Proxy:ERROR^[[0m: endpoints.py:121 - litellm.proxy.proxy_server.anthropic_response(): Exception occured - litellm.InternalServerError: InternalServerError: Hosted_vllmException - Header value must be str or bytes, not <class 'float'>. Received Model Group=kimi-k2.6
2026-05-08T12:21:49.200762885+02:00 stderr F Available Model Group Fallbacks=None LiteLLM Retried: 2 times, LiteLLM Max Retries: 2
2026-05-08T12:21:49.200768846+02:00 stderr F Traceback (most recent call last):
2026-05-08T12:21:49.200773695+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/litellm/llms/custom_httpx/llm_http_handler.py", line 180, in _make_common_async_call
2026-05-08T12:21:49.200778404+02:00 stderr F     response = await async_httpx_client.post(
2026-05-08T12:21:49.200782983+02:00 stderr F                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2026-05-08T12:21:49.200788603+02:00 stderr F     ...<10 lines>...
2026-05-08T12:21:49.20079255+02:00 stderr F     )
2026-05-08T12:21:49.200796498+02:00 stderr F     ^
2026-05-08T12:21:49.200801327+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/litellm/litellm_core_utils/logging_utils.py", line 297, in async_wrapper
2026-05-08T12:21:49.200805655+02:00 stderr F     result = await func(*args, **kwargs)
2026-05-08T12:21:49.200809532+02:00 stderr F              ^^^^^^^^^^^^^^^^^^^^^^^^^^^
2026-05-08T12:21:49.200815634+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/litellm/llms/custom_httpx/http_handler.py", line 576, in post
2026-05-08T12:21:49.200820112+02:00 stderr F     raise e
2026-05-08T12:21:49.20082429+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/litellm/llms/custom_httpx/http_handler.py", line 527, in post
2026-05-08T12:21:49.200850859+02:00 stderr F     req = self.client.build_request(
2026-05-08T12:21:49.200854155+02:00 stderr F         "POST",
2026-05-08T12:21:49.20085695+02:00 stderr F     ...<7 lines>...
2026-05-08T12:21:49.200860247+02:00 stderr F         content=request_content,
2026-05-08T12:21:49.200863192+02:00 stderr F     )
2026-05-08T12:21:49.200865907+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/httpx/_client.py", line 367, in build_request
2026-05-08T12:21:49.200869183+02:00 stderr F     headers = self._merge_headers(headers)
2026-05-08T12:21:49.200872049+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/httpx/_client.py", line 430, in _merge_headers
2026-05-08T12:21:49.200874623+02:00 stderr F     merged_headers.update(headers)
2026-05-08T12:21:49.200877469+02:00 stderr F     ~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^
2026-05-08T12:21:49.200880034+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/httpx/_models.py", line 275, in update
2026-05-08T12:21:49.200882618+02:00 stderr F     headers = Headers(headers)
2026-05-08T12:21:49.200885203+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/httpx/_models.py", line 156, in __init__
2026-05-08T12:21:49.200888439+02:00 stderr F     bytes_value = _normalize_header_value(v, encoding)
2026-05-08T12:21:49.200891284+02:00 stderr F   File "/app/.venv/lib/python3.13/site-packages/httpx/_models.py", line 81, in _normalize_header_value
2026-05-08T12:21:49.2008945+02:00 stderr F     raise TypeError(f"Header value must be str or bytes, not {type(value)}")
2026-05-08T12:21:49.200897206+02:00 stderr F TypeError: Header value must be str or bytes, not <class 'float'>

---

proxy_config:
  model_list: {}
  general_settings:
    background_health_checks: False
    forward_client_headers_to_llm_api: True
    use_shared_health_check: True
    use_redis_transaction_buffer: true
    health_check_interval: 300
    use_x_forwarded_for: True
    master_key: os.environ/PROXY_MASTER_KEY
    user_header_mappings:
    - header_name: "x-openwebui-user-email"
      litellm_user_role: internal_user
  litellm_settings:
    add_user_information_to_llm_headers: true
    drop_params: true
    modify_params: true
    redact_user_api_key_info: True
    extra_spend_tag_headers:
    - "x-openwebui-user-email"
    cache: True
    cache_params:
      type: redis
      host: litellm-redis
      port: 6379
  router_settings:
    routing_strategy: least-busy
    redis_host: os.environ/REDIS_HOST
    redis_port: os.environ/REDIS_PORT

---