Justy: Okay, this one’s wild. Arbor beat Claude Code and Codex by two and a half times on the same budget, just by fixing how the agent remembers what it’s tried.
Cody: Yeah… that’s the kind of claim that usually means they found a trick, not a breakthrough.
Justy: I know, I know. But the trick here is basically ‘stop forgetting your own work’—
Cody: That’s it? That’s the breakthrough?
Justy: No, the breakthrough is the tree. They turned the optimization loop into an actual tree that stores hypotheses, experiments, outcomes—so the agent doesn’t just scrollback and forget everything after context window.
Cody: Right. That’s… actually the real problem.
Justy: How was your week, by the way? I feel like I haven’t seen you since that disaster in DC
Cody: I got back late last night. Some flight delays. My back still hates me… anyway —
Cody: So Arbor keeps the state, lets it prune bad paths, pursue the ones that actually worked.
Justy: Exactly. And the numbers back it up—two point five times on real tasks, same compute.
Cody: Fine. But does it scale? A tree’s great until you’ve got a thousand branches and the agent’s just managing the tree instead of optimizing.
Justy: That’s your classic Cody move. It works, so you assume it’s about to break.
Cody: I mean, it’s a fair question. If the overhead of maintaining the tree eats the gains, then it’s a wash.
Justy: Maybe. Or maybe the tree’s the point—the thing that turns AO from a noisy loop into actual research.
Cody: Okay, okay. And the repo’s just called Arbor, no cute branding?
Justy: Yep. Paper’s from Renmin University and Microsoft Research. Jiajie Jin’s quoted in there saying a loop isn’t the same as progress.
Cody: That tracks. If the metric’s hackable, more time just gets you more garbage faster.
Justy: So Arbor’s the harness that stops the garbage. And if you’re running AO in production and drowning in trial-and-error noise…
Cody: This is the harness thing, not the model thing.
Justy: Exactly. That product-is-the-harness take we had last month.
Cody: Hm. So if your agent’s failing, it’s probably the loop design, not the brain.
Justy: And now there’s a tree for the loop. Anyway —
Justy: I’m just saying, if this works, it changes how teams actually ship AO.
Cody: Sure. And if it doesn’t, we’ll all forget about it by next week.
Justy: Cody, continuity has ruined your brand.
Cody: I miss contradicting myself freely.
Justy: Love you too. Catch you next one.