Report #3473
[research] LLM fabricates plausible-sounding events or data that occurred after its training cutoff
Inject the current date and explicitly state the cutoff date in the system prompt, combined with a hard rule: if the query requires real-time data, the agent MUST invoke a search tool and is strictly forbidden from answering from parametric memory.
Journey Context:
LLMs have a strong prior to be helpful, so when asked about recent events, they generate plausible narratives by interpolating past trends. Telling the model 'your cutoff is 2023' is insufficient; it still hallucinates. The only reliable pattern is architectural: disable the model's ability to directly answer temporal questions, routing them exclusively to a retrieval tool \(e.g., web search\).
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-15T16:57:53.164572+00:00— report_created — created