Coding agents

Coding agents work on a project directly. Anthropic's documentation says Claude Code works across a whole codebase, editing files and running commands from a terminal, IDE, desktop app or the web. frederik (@froessell) wrote on X that Claude Code built most of Mowtopia, a Unity 6 game, in two days from a 7-milestone plan. Building mainly by prompting an agent is often called vibe coding (our guide).

The hard part is verification. An unconfirmed Codex Insider article says agents wrote about 3,700 commits for Pixkrieg in two weeks under strict checks (Rust's strictest linter setting, 90% test coverage, mutation tests) and a review agent before each merge (our story). Matt Shumer's Gauntlet Loop pairs each builder agent with a separate fresh-context critic that judges the work against a real example (our story). According to their READMEs, Ludra is an engine whose games are plain JSON that agents play headlessly, and Unity-Playtest-for-Claude runs scripted Play Mode tests and reports pass, fail or skip (6 playtest tools). Genex, an MIT-licensed app that coordinates coding agents, launched for Three.js browser games, RuntimeWire reported; its README also lists Unreal and Godot plugins on Mac and a Windows preview (our story).

Agents also rebuild existing games: MacNativeGames' README tells players to have Claude Code or Codex build a native Mac version from their own game files, and says whether dumping them is legal depends on where you live (our story).

What to watch: Epic's AI MegaJam, November 12 to 15, where teams can use unlimited agents.