{"version":"2.1.312","anchor":"date-attachment-carries-assumedutc-and-uses-the-corrected-da","canonical_anchor":"date-attachment-carries-assumedutc-and-uses-the-corrected-da","heading":"The date Claude is told can now be flagged as assumed to be UTC","tier":"internal","area":"System Prompt","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.312\/e\/date-attachment-carries-assumedutc-and-uses-the-corrected-da","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.312","markdown":"### The date Claude is told can now be flagged as assumed to be UTC\n\nThe current date Claude Code passes to Claude can now carry a mark saying it was worked out assuming the UTC time zone\n\n**Unclear.** What makes Claude Code assume UTC for the date is not stated.\n\n**What**\n\nClaude Code tells Claude the current date. That date note can now carry two extra pieces of information:\n\n- A mark saying the date was worked out assuming the UTC time zone, added only when a certain condition holds.\n\n- An optional note that the date has changed.\n\nBefore, the note held only the date. When building the date note fails, Claude Code now also logs the right error.\n\n**Why**\n\nClaude may be told when the date it was given rests on an assumed UTC time zone.\n\n- Area: System Prompt\n- Tier: Under the hood\n- Useful: 2\/5\n- Signal: 2\/5\n- Scope: individual\n- Heads-up: no"}