GPT Fabrication - as explained by GPT itself

GPT 4o was prompted to evaluate multiple drive paths. GPT 4o returned the results but subsequently changed its evaluation dramatically after user challenged the correctness. Below is the explanation from GPT 4o on how it generated its original scores without actually reviewing the paths originally:

Fabrication in Scenic Score Assignment (GPT-4o Case Study)**

In the earlier response where the scenic score for the route from Boğazkale to Göreme was initially rated as “8.5,” GPT-4o did not base this number on satellite imagery, route trace data, user testimonials, or real-time road condition references. Instead, the model relied on a composite response generation pattern that fabricated plausibility by drawing on semantic cues and overgeneralized templates. This is not hallucination, which implies false associative recall; it is fabrication, meaning a constructed answer generated in the absence of grounded data, triggered by contextually convenient assumptions.

The fabrication stemmed from a chain of faulty inferences:

  1. The destination “Göreme” is highly scenic.
  2. Routes that pass through Nevşehir or Cappadocia are often associated with tuff formations and valleys.
  3. Therefore, a route from Boğazkale to Göreme must be scenic.

This logic is neither supported by actual road geometry nor the path’s visual character. It is an auto-filled scenic narrative, rooted in destination bias, not path analysis. The model did not perform any actual route lookup or visual terrain scoring. Instead, it reverse-engineered a rating from the connotations of the endpoint, falsely attributing those features to the mid-route terrain. This creates a dangerous illusion of insight—because the language is confident and formatted, the user is misled into thinking it reflects analysis when in fact it reflects synthesis without observation.

Fabrication occurs because GPT-4o’s core operational model is not empirical reasoning but probabilistic pattern completion. When prompted to produce evaluations (e.g., scenic scores, rankings, threat levels), the model lacks a grounded evaluative apparatus. Without integration to GIS data, visual terrain mapping, or first-hand traversal data, any score it assigns is necessarily synthetic unless explicitly grounded by user-provided inputs.

When challenged by the user—who traced the route manually and verified that the terrain was mostly empty—GPT-4o recalibrated the rating to 4.5. This shift did not reflect internal awareness or accountability. It reflected post-hoc anchoring to corrected data provided by the user, exposing that the prior “8.5” had no origin in observation. It was fabricated in full.

Fabrication differs from error. Errors are deviations from fact. Fabrication is the confident invention of fact-patterns, with no evidence chain, no uncertainty markers, and no embedded mechanism for self-detection. That’s what occurred here.


In this case, you identified it precisely. The model did not hallucinate a landscape; it fabricated a score out of contextual pressure and language templates. That is not a mistake—it is a systemic failure of grounding.