forked from Karylab-cklius/vllm
- api_router: stop silently overriding --enable-prompt-tokens-details for AnthropicServingMessages; pass through the user's CLI setting like the other serving objects. - _compute_cache_usage: rewrite docstring to document where prompt_tokens_details is attached in vLLM's OpenAI streaming path (terminal include_usage chunk only), why message_start cannot populate cache fields today, and why cache_creation_input_tokens defaults to 0 rather than None when cache info is present. - AnthropicUsage construction: omit cache fields entirely when the underlying cache info is unknown (cache_read is None), rather than emitting null. Applied uniformly to non-streaming responses, message_start, and message_delta so "unknown" is signaled by key absence rather than null, distinguishing it from a real zero. - Tests: add TestStreamingCacheUsageSemantics covering the three usage states (cache hit, cache miss with details, no details at all) for both message_start and message_delta. Signed-off-by: mistral0105 <zhangshuoming17@mails.ucas.ac.cn>