Agent tooling is hardening around terminals, sims and validation

Herdr shipped a native app (50298436), a terminal multiplexer built around coding agents. One user switched after a decade of tmux, and others immediately asked how it compares to CMUX. Simantic (YC F26) launched firmware simulation for AI agents (50291116). Its pitch, echoed by a commenter working on agent tooling, is that generation got fast and cheap but validation didn't. Someone asked why it's a cloud service and not a local emulator. A swarm experiment in Minecraft and Mindustry (50296486) found agents acting almost turn-based, with a hierarchy set by alphabetical order, which readers called a weak setup. A 60-year-old in 47282777 says Claude Code re-ignited his passion, and others describe it as programming with a few buddies who occasionally wreck everything.

The pattern: the interesting startups are no longer the model, they're the harness. Where agents write code, the bottleneck moves to checking it, whether that's a firmware simulator or a better session manager. Another commenter said Claude Code felt unfulfilling after two days at work, so the experience isn't universal.