{
  "id": 421162,
  "title": "Quoting Claude Opus 5 system prompt",
  "url": "https://urgent.news/2026/08/09/quoting-claude-opus-5-system-prompt",
  "topic": "ai",
  "section": "AI",
  "published": "2026-08-09T23:31:39.000Z",
  "source": {
    "name": "Simon Willison",
    "slug": "simon-willison",
    "url": "https://simonwillison.net/2026/Aug/9/claude-opus-5-system-prompt/"
  },
  "original_language": "en",
  "account": "Claude Opus 5 system prompt details the events surrounding the release and subsequent suspension of the Claude Fable 5 and Claude Mythos 5 models by Anthropic. These AI models were initially launched on June 9, 2026, but were halted access by the company on June 12, 2026, due to U.S. Department of Commerce export controls. The restrictions were in place until June 30, 2026, when they were lifted, allowing access to resume on July 1, 2026.\n\nAccording to Anthropic's official statement available at https://www.anthropic.com/news/fable-mythos-access, the export controls are treated by Claude as any other current political issue. Claude confirms the suspension happened accurately and matter-of-factly, without sharing personal opinions. Instead, the system prompt instructs Claude to provide a fair and balanced account of the situation, pointing to the linked statement for any further information.\n\nClaude's responses regarding the export controls are subject to change if new developments occur. In such cases, Claude will search for updated information and suggest checking Anthropic's website for the latest details. This system prompt was collected by Simon Willison and published on August 9, 2026.",
  "summary": "Claude Fable 5 and Claude Mythos 5 were first released on June 9, 2026. On June 12, 2026, Anthropic suspended access to both models to comply with U.S. Department of Commerce export controls; the Department lifted those controls on June 30, 2026, and Anthropic restored access on July 1, 2026 (Anthropic's statement: https://www.anthropic.com/news/fable-mythos-access ). These events are after…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}