{"slug": "breaking-openai-prompt-cache-options-is-no-longer-accepted", "title": "OpenAI: prompt_cache_options is no longer accepted", "summary": "OpenAI's published API specification no longer includes the prompt_cache_options field on CreateModelResponseProperties, affecting two OpenAI operations, according to an API-change report. The field is now ignored rather than rejected, so calls that still send prompt_cache_options succeed but behave differently, and the report advises developers to grep their code for the parameter. BetaCreateModelResponseProperties.prompt_cache_options was also removed.", "body_md": "## What changed\n\nUsually ignored rather than rejected, so the call succeeds and does something subtly different.\n\nAffects `prompt_cache_options` on `CreateModelResponseProperties` reachable from 2 operations. Grep for it: nothing else will tell you.\n\n## Who is affected\n\nCode that sends OpenAI's CreateModelResponseProperties objects, used by 2 OpenAI operations.\n\n## Before and after\n\n| Where | Before | After | \n|---|---|---|\n| CreateModelResponseProperties.prompt_cache_options | present | absent | \n| BetaCreateModelResponseProperties.prompt_cache_options | present | absent | \n\n## Code that breaks\n\n```\nawait client.post(\"/…\", {\n  // prompt_cache_options is now ignored, not rejected\n  prompt_cache_options: value,\n});\n```\n\nBased on OpenAI’s published API specification. [How severity is decided](https://driftwatch.et/method).", "url": "https://wpnews.pro/news/breaking-openai-prompt-cache-options-is-no-longer-accepted", "canonical_source": "https://driftwatch.et/changes/openai-2026-11-03-7094f95d", "published_at": "2026-11-03 22:29:31+00:00", "updated_at": "2026-11-04 00:20:22.643743+00:00", "lang": "en", "topics": ["ai-tools", "developer-tools", "large-language-models"], "entities": ["OpenAI", "CreateModelResponseProperties", "BetaCreateModelResponseProperties", "prompt_cache_options"], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/breaking-openai-prompt-cache-options-is-no-longer-accepted", "markdown": "https://wpnews.pro/news/breaking-openai-prompt-cache-options-is-no-longer-accepted.md", "text": "https://wpnews.pro/news/breaking-openai-prompt-cache-options-is-no-longer-accepted.txt", "jsonld": "https://wpnews.pro/news/breaking-openai-prompt-cache-options-is-no-longer-accepted.jsonld"}}