# GPT 6.1 Sol seems to do worse on long-tail languages.

> Source: <https://micjm.com/blog/gpt-6.1-sol-long-tail-languages/>
> Published: 2026-11-13 22:41:09+00:00

[srcreigh](https://news.ycombinator.com/user?id=srcreigh) wrote in a [Hacker News comment](https://news.ycombinator.com/item?id=50489509):

The ideal language is the one the agent knows how to use.

I used prolog for a project and GPT 6.1 Sol repeatedly made dumb mistakes as if it doesn’t understand the symbolic resolution capabilities.

That made me curious: does Sol do worse when it’s working outside the usual programming languages?

We have some data to look at! We’re working on a [battle system for OpenCode](https://github.com/bottomless/agent-duel), which lets users compare models on their actual tasks. I used [Jev](https://openrouter.ai/docs/guides/community/jev) to tag the programming languages in all 712 Sol battles, using the requests and available conversation context without showing it the outcomes.