Definition
Plain language
A bare-bones AI math agent that just iterates with a language model and a proof checker.
As stated in the literature
The simplest agent variant in the DeepMind Erdős work: a Ralph-style loop pairing an LLM (Gemini 3.1 Pro) with the Lean compiler, no evolution or AlphaProof, run in parallel until a proof compiles.
Also called: Agent B, Agent C, Agent D
Why it matters: It's a useful baseline showing how much pure repetition with a strong model and a verifier can accomplish, before any sophisticated search is added.
For example, Agent A just keeps asking Gemini to write a Lean proof, checks it with the compiler, and repeats — no fancy search.
Heard on the show
“Agent A has a cleanup job: a bad rollout left a bunch of services running the wrong container image, and A has to find every affected service and restore the correct image.”Episode 150 — Don't Kill the Loser: A Different Way to Handle Two AI Agents Colliding