opus 4.6 and two small tools

06 Feb 2026

Opus 4.6 came out ~20 hours ago and I wanted to get a feel for it. It also seemed like a good chance to follow up on some of the ideas from my previous post — specifically, building small tools that help me stay more engaged with my own work rather than just producing output.¹

Opus 4.6

The experience isn’t wildly different from Opus 4.5, but the edges are smoother in ways that matter. It picks up intent faster: I found myself spending less time explaining what I wanted, which over a full session adds up. It seems more inclined toward longer time-horizon tasks, willing to loop and think for >8 minutes before surfacing an answer, and it spawns multiple sub-agents more readily out of the box without much coaxing.² I haven’t tried the full agent teams thing yet, but the multi-agent orchestration feels like it’s gotten significantly less fiddly.

The thing I noticed most was the quality of the questions. When I used it in an interview-style flow, the questions felt more to the point and more thoughtful — less of the “asking just because” quality I’d sometimes get before, where it seemed like the model was generating questions for the sake of generating questions. I wonder if they invested time specifically in making it interview better.

the things I built

I’ve been wanting to use the interview format more deliberately (AI as an interlocutor rather than a doer thing), where you’re still doing the cognitive work but something is prompting you to externalize and refine your thinking. So making that more convenient seemed like a natural place to start.

I went looking for existing interview-style plugins.³ The well-known ones⁴ weren’t quite what I was after — they tend toward exhaustive question lists without much ability to steer the process. What I wanted was a checkpoint mechanism: every few questions, pause and let me say “we’re too deep in the details” or “not deep enough.” The ability to tune the depth as you go, depending on what the task actually needs. The result is here — it’s a Claude Code command, nothing fancy, but it strikes a balance I’m happy with.

The second tool came from a pattern I’ve been noticing in my day-to-day. Markdowns are everywhere (specs, plans, research notes) and I kept finding myself needing to go over an LLM-generated markdown and provide detailed feedback before continuing. I was doing this by manually annotating raw .md files in VSCode or nano, which isn’t great when you want to see the rendered version and annotate on it at the same time. So I built Marginalia, a small SPA that lets you view rendered markdown and add margin annotations.⁵ No sessions, no backend — it just lives in the browser. It’s a one-off tool for a specific friction point, the moment where you need to actually engage with what came back rather than staying in the “fix it plz” loop.

I think both of these are attempts to take the stuff that’s been living in my head (about staying engaged, about not outsourcing the thinking) and work it into my actual day-to-day (whether they end up being useful beyond my own workflow, I don’t know, but the links are there if anyone wants to try them).

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