{"name":"CLAUDE_CODE_QUESTION_PREVIEW_FORMAT","slug":"claude-code-question-preview-format","family":"env","title":"Environment variables","noun":"environment variable","description":"Sets the `AskUserQuestion` preview format when the value is `markdown` or `html`. Otherwise `markdown` is chosen for clients other than SDK, `claude-desktop`, `local-agent`, `remote` and some VS Code sessions. The SDK sets this variable for the CLI process from its `askUserQuestion.previewFormat` option.","description_source":"code","described_by":{"bundle":"2.1.286","author":"claude-opus-5-5"},"presence":{"first_seen":"2.1.138","removed_in":null,"in_current_build":true,"newest_mined":"2.1.308","builds":149,"mined_builds":149,"first_cited":{"version":"2.1.119","released_at":"2026-04-23 21:36:46","spans":1}},"aliases":[],"entries":[{"version":"2.1.119","anchor":"sdk-enhancements","heading":"SDK Enhancements","line":null,"released_at":"2026-04-23 21:36:46","reason":"found in this entry's text"}],"entries_total":1,"docs":[],"docs_total":0,"gates":[],"related":[{"name":"CLAUDE_CODE_QUESTION_EXTENDED","slug":"claude-code-question-extended","description":"An extended question mode is gated behind an env var and off by default."},{"name":"CLAUDE_CODE_QUESTION_OPTIONAL_DESCRIPTIONS","slug":"claude-code-question-optional-descriptions","description":"New CLAUDE_CODE_QUESTION_OPTIONAL_DESCRIPTIONS env var makes AskUserQuestion option descriptions optional, but only for certain entrypoints"}],"url":"https:\/\/changelogs.core-directive.com\/reference\/env\/claude-code-question-preview-format","family_url":"https:\/\/changelogs.core-directive.com\/reference\/env.json"}