{"schema_version":"kingy-change-evidence-v1","event":{"id":"ct-79ba2341faed4ef7c9d4fd18","vendor":"OpenAI","category":"changelog","type":"documented_source_change","title":"OpenAI API changelog documentation changed","source_id":"openai-changelog","source_url":"https://developers.openai.com/api/docs/changelog.md","observed_at":"2026-10-20T19:55:07Z","last_unchanged_at":"2026-10-20T17:50:08Z","before_snapshot":"snap-bf087a5535904194d892de5c6ced","after_snapshot":"snap-ae4bdf92dbffc937039b77a4d43b","before_hash":"51d96059b0cf06e5141c137b45fe1a729969b8eb37ada7905995ba0056c8b47c","after_hash":"8c91d390bec4addbd0b2b845aa37a725a007df82a0590cca1048988af2a3c1c6","before_excerpt":"","after_excerpt":"### Oct 20 Feature · API: v1/responses You can now choose 12-hour prompt caching in the API. 12-hour prompt caching keeps shared instructions, tools, and context cached longer to benefit from lower cached-input pricing, even when requests are hours apart. 12-hour cache writes cost 2.5x the input token price. Read more [here](https://developers.openai.com/api/docs/guides/prompt-caching). ### Oct 16 Feature · API: v1/agents [OpenAI-hosted sandboxes](https://developers.openai.com/api/docs/guides/agents-api/environments/openai-hosted) in the Agents API now include the Artifact SDK and skills for creating and editing spreadsheets, presentations, and Word documents. Added [Ultrafast mode](https://developers.openai.com/api/docs/guides/ultrafast-mode) to the Agents API. Set `agent.service_tier` …","status":"published","scope":"Published documentation; runtime behavior and legal interpretation not established.","before_capture":{"http_status":304,"resolved_url":"https://developers.openai.com/api/docs/changelog.md","etag":"\"3549d848814ad273012a1dfde1b2dc33\"","last_modified":"Fri, 16 Oct 2026 18:05:06 GMT","source_id":"openai-changelog","source_url":"https://developers.openai.com/api/docs/changelog.md","captured_at":"2026-10-20T17:50:08Z","raw_sha256":"51d96059b0cf06e5141c137b45fe1a729969b8eb37ada7905995ba0056c8b47c","normalized_sha256":"2fecb93b26ae50bcc5eaf17ad5dc90619f624c3bf06da95e41782d85fec10c39","collector_version":"1.0.0","normalizer_version":"1.1","locale":"en-US","collection_region":"existing hosting; account-independent public request","id":"snap-bf087a5535904194d892de5c6ced"},"after_capture":{"http_status":200,"resolved_url":"https://developers.openai.com/api/docs/changelog.md","etag":"\"8eba3540b91d930a03b05106a15909f9\"","last_modified":"Tue, 20 Oct 2026 19:48:38 GMT","response_date":"Tue, 20 Oct 2026 19:55:07 GMT","source_id":"openai-changelog","source_url":"https://developers.openai.com/api/docs/changelog.md","captured_at":"2026-10-20T19:55:07Z","raw_sha256":"8c91d390bec4addbd0b2b845aa37a725a007df82a0590cca1048988af2a3c1c6","normalized_sha256":"b5aeffe23b60df49c00d6fd3f0ed3f5a0dc9855988cfd855981cd6112e01bc44","collector_version":"1.0.0","normalizer_version":"1.1","locale":"en-US","collection_region":"existing hosting; account-independent public request","id":"snap-ae4bdf92dbffc937039b77a4d43b"},"display_normalizer_version":"1.1","display_before_sha256":"2fecb93b26ae50bcc5eaf17ad5dc90619f624c3bf06da95e41782d85fec10c39","display_after_sha256":"b5aeffe23b60df49c00d6fd3f0ed3f5a0dc9855988cfd855981cd6112e01bc44"},"content_scope":"Changed excerpts and retained capture metadata; complete raw responses archived privately"}