---
title: "Why Michelin switched off GitHub Copilot's Auto mode — Marsanne Studio AI watch"
description: "Michelin disabled automatic model selection by default on GitHub Copilot after a 700-request experiment revealed unpredictable and costly routing."
url: "https://marsanne.studio/en/ai-watch/why-michelin-switched-off-github-copilot-s-auto-69e8ca/"
lang: "en"
---

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Case study · 21 September 2026

# Why Michelin switched off GitHub Copilot's Auto mode

Original title, in French: “Pourquoi Michelin a coupé le mode Auto de GitHub Copilot”

**Publication**

Silicon.fr (France)

**Author**

Clément Bohic

**Published on**

21 September 2026 · read in the page structured data · updated on 22 September 2026

## Summary

Michelin details an experiment conducted on around 700 requests to evaluate GitHub Copilot's Auto mode, which automatically selects an AI model using a classifier based on four criteria. The company found that this classifier analyses words rather than the actual context of tasks, leading to a model choice that is sometimes random and to large cost differences (from 0.23 to 3.24 credits for the same request). Michelin also shows that the 10% discount promised by GitHub does not always offset the additional cost of Auto mode, notably in chat sessions. The company considers that a cheaper model (GPT Luna) delivers equivalent results for single tasks, and describes Auto mode as a "safety net" rather than a source of savings. An experimental orchestrator, HydraFusion, proves significantly more expensive.

Summary based on the full text of the article.

[Read the article on Silicon.fr →](https://www.silicon.fr/data-ia-1372/michelin-github-copilot-mode-auto-229220)

## Figures cited

-   0.23 credit
    
    Cost of a variable renaming request with MAI-Flash
    
    Michelin test on GitHub Copilot
    
    > « Avec le premier, il en a coûté 0,23 crédit. »
    
-   3.24 credit
    
    Cost of a variable renaming request with GPT-5.6 Terra
    
    Michelin test on GitHub Copilot
    
    > « Avec le second, 3,24. »
    
-   11.9 %
    
    Average Auto mode discount with the same model (Claude Sonnet 5)
    
    6 requests tested by Michelin
    
    > « sur 6 requêtes, 11,9 % moins cher en moyenne »
    
-   13.7 credit
    
    Average cost of a chat session opened with a difficult question
    
    Michelin test, 7-turn sessions
    
    > « pour un coût moyen de 13,7 crédits »
    
-   0.78 credit
    
    Average cost of a chat session opened with a simple question
    
    Michelin test, 7-turn sessions
    
    > « pour un coût moyen de 0,78 crédit »
    
-   28 credit
    
    Additional cost of HydraFusion compared with Auto mode for a cascading task
    
    Michelin test, HydraFusion vs Auto mode
    
    > « Il en a coûté 16 et 28 crédits, là où le mode Auto en aurait consommé 3. »
    

## Classification

**Country**

France

**Company size**

Large companies

**Industries**

Industry and manufacturing · Software vendors, IT services companies, telecoms

**Companies**

GitHub (supplier), Michelin (deploys AI)

**Keywords**

github copilot, generative artificial intelligence, AI costs, software development, model routing, AI optimisation

Entry written by Marsanne Studio from the cited article, with the help of an AI model (claude-sonnet-5). The rights to the article and its illustrations belong to Silicon.fr and its author. Entry translated from French by Claude Sonnet 5.5.