Alex Duffy's post on X, curated on eChai

Curated from X →

Alex Duffy runs Goodstart Labs, which builds learning environments for agents and needs every action graded. On their sample Jev agreed with Fable 5.1 nine times in ten, at about 200 times lower grading cost and under half a second a call. Erik Gafni, named in the post, is one of TypeSafe's three co-founders.

Alex Duffy 16 Sep 2026

Awesome to see @EGafni & Diogo launch their first model Jev!

Verification is the bottleneck for building great AI learning environments. Jev is a welcome, unique, addition to our toolkit @goodstartlabs

Typed decisions,
probabilities for each option,
free output tokens!

On our sample:
• Jev agreed with Fable 5.1 nine times out of ten
• ~200× lower grading cost
• <0.5 seconds per grading call

That means more eyes on what agents are doing and what we’re teaching them.

More on how we’re using it to build game environments, experts to play them, and ensuring they teach the right things:
goodstartlabs.com Verification is the bottleneck

More Founder Notes

A
Aditi Singh 16h

☕ An evening at AI Café by eChai Ventures x House of Starts!

It was a great space to connect with founders, students and people from diverse backgrounds who are interested in AI and building something with it. The conversations, exchange of ideas and the demo & pitch session made it a really interesting experience, especially seeing how people are exploring AI in their work and products.

Definitely a Friday well spent! ✨

Originally on LinkedIn →
Curated from X →

Andre Landgraf's showcase of the yes/no gate, several worked examples at the link.

Andre Landgraf 1d

Ok, jev is really cool. So many great use cases where a fast and accurate yes/no gate can deliver meaningful performance gains.

Played around and built some showcase examples here →
safer-with-jev.com Safer with Jev
Curated from X →

Vipul Sharma's Minecraft agents ask Jev whether to fight or run, from what the agent can see, the mob count, its weapon and its health; one broke off mid-fight as the odds turned.

Vipul Sharma 1d

I hooked up Jev by @typesafeai to a few agents on my Minecraft world. Look at how Jev decides when they should fight and when they should run away.

Jev rates the odds from what the agent can see, mob count, weapon, how hurt it is, and runs away when they are bad. One broke off mid-fight as its odds turned.

eChai Partner Brands The partnership →