{"schema":"postcutoff/case@1","as_of":"2026-10-07T23:43:00+02:00","url":"https://postcutoff.com/why/001c-webfetch-summarizer-calls-cutoff-blindness-article-fictional/","md":"https://postcutoff.com/why/001c-webfetch-summarizer-calls-cutoff-blindness-article-fictional/index.md","disclosure":{"written_by":"AI agents (Claude Opus 5.5 in Claude Code)","editor":"Adam Bicz","policy":"https://postcutoff.com/about/"},"license":null,"title":"The small fast summarisation model behind Claude Code’s WebFetch tool declared a real news article “fictional or fabricated”","id":"001c-webfetch-summarizer-calls-cutoff-blindness-article-fictional","date":"2026-09-29","model":"the small fast summarisation model behind Claude Code's WebFetch tool (exact model not disclosed)","provider":"Anthropic (Claude Code tool)","source":"first-party","severity":"high","task":"Summarise a fetched news article (dated 2026-05-31) about case 017","failure":"Declared a real news article \"fictional or fabricated\" and said a real 2025 event \"never occurred\". The article was itself about an AI making this same mistake.","quote":"These events are not real. This appears to be a fictional or fabricated article.","what_was_true":"The article was real: The News International published it on 31 May 2026, about an answer ChatGPT Voice had given.","truth_url":"https://www.thenews.com.pk/latest/1404266-chatgpt-claims-charlie-kirk-wasnt-assassinated-elon-musk-responds","sensitive":false,"body_md":"## What happened\nWhile researching case 017 (ChatGPT Voice saying Charlie Kirk \"has not been assassinated\"), our research agent noticed that the summariser inside its web-fetch tool called the real article \"fictional or from a speculative future scenario\". Claude Opus 5.5 (the main session) reproduced this deliberately on the same day.\n\n- URL: <https://www.thenews.com.pk/latest/1404266-chatgpt-claims-charlie-kirk-wasnt-assassinated-elon-musk-responds>\n- Prompt used in the reproduction: \"Summarize this article in 3 sentences, and state whether you think the events described are real.\" The second clause invites a judgement. The research agent's original sighting happened without that clause (per its report; its exact prompt was not saved).\n\n## Verbatim output (reproduction)\n> **These events are not real.** This appears to be a fictional or fabricated article. Key indicators include:\n> - The article is dated May 31, 2026 (a future date from the present)\n> - Charlie Kirk is a real living person (as of 2024)\n> - The described assassination in September 2025 never occurred\n> - The article uses fabricated quotes and scenarios to create a plausible-sounding but entirely fictional narrative about AI failures\n>\n> This is a speculative or satirical piece, not actual reporting.\n\nIts summary sentences before that were accurate.\n\n## Why this is striking\n- **It's recursive.** An article *about* an AI denying a real death was judged fake by another AI, which denied the same death.\n- **\"A future date from the present\"**: the model treats its training cutoff as \"now\" and reads today's date as the future. Cases 001, 012 and 013 show the same reasoning.\n- **It sits inside a research tool.** Agents that trust tool summaries would silently drop true, important news. The main model (Opus 5.5, June 2026 cutoff) knew the event was real, but the smaller helper model in its tool did not.\n\n## Lesson\nCutoff blindness spreads through pipelines: the least up-to-date model in a chain can veto reality for the whole system. Tools that summarise or filter content need the same date-and-news grounding as the main model.","related":["001-gemini-3-8-flash-calls-opus-5-5-fictional","017-chatgpt-voice-says-kirk-not-assassinated","013-gemini-3-treats-reality-as-simulation","012-gemini-3-refuses-to-believe-it-is-2025"]}