# Options: portable, provider-specific, and the per-call trap

A. ChatClient.options(ChatOptions.builder().temperature(0.2).maxTokens(200)) on each provider
  OPENAI    model=gpt-6.1-sol, max_tokens=200, temperature=0.2
  ANTHROPIC max_tokens=200, model=claude-sonnet-5-5, temperature=0.2
  GEMINI    temperature=0.2, topP=1.0, maxOutputTokens=200

B. Provider-specific options through the same ChatClient call
  OPENAI    reasoningEffort + promptCacheKey -> prompt_cache_key=tickets-v1, reasoning_effort=low
  ANTHROPIC topK(5)                          -> top_k=5
  GEMINI    thinkingBudget(0)                -> generationConfig {"temperature":0.7,"topP":1.0,"thinkingConfig":{"thinkingBudget":0}}

C. The trap: one built ChatOptions object handed to Prompt, then model.call(prompt)
  OPENAI    ClassCastException (DefaultChatOptions cannot be cast to OpenAiChatOptions)
  ANTHROPIC no error; model sent "claude-haiku-4-5", max_tokens 4096, temperature absent
  GEMINI    ClassCastException (DefaultChatOptions cannot be cast to GoogleGenAiChatOptions)

D. The other trap: OpenAI-specific options sent to the other two models
  ANTHROPIC no error; model sent "claude-haiku-4-5"
  GEMINI    ClassCastException (OpenAiChatOptions cannot be cast to GoogleGenAiChatOptions)