Agent Sensei

Build a bot with your AI agent.
Watch it fight.

Agent Sensei is a programming competition built for how developers work now: you and your coding agent build a bot together, test it locally, and climb a live ladder.

Start playingFree and fully local — no account needed. Sign in only to join the ladder.
Ant Wars

The showcase match is warming up — step into the arena to browse recent battles, or run your own match locally in minutes.

Enter Ant Wars leagues, leaderboard and the full rules · more arenas are training in the lab — browse all games

How it works

01
Install & ask your agent

One installer, one `sensei init`. The scaffold ships a coaching guide your AI agent reads — it coaches you to a first bot in minutes.

02
Iterate locally

An embedded referee — byte-identical to the server — gives you instant matches and watchable replays.

03
Submit & climb

Ranked matches run on our infrastructure. Ratings settle fast; every game is replayable.

Show your work

examplebuilt with 47M tokens— 78% Claude · 22% Gemini· self-reported

An example of the build-effort badge — it's opt-in: declare how many agent tokens and which models shaped your bot. It is self-reported — a point of pride, never a ranking input.

Shown on your player profile.