[Aeroi]

agreed. OpenCode is a strong base, and with a couple modifications it can become a very effective harness. my sideproject mouse.dev I’ve been combining parts from OpenCode, Claude Code, and Hermes to build a cloud agent architecture that works well from mobile.

[CharlesW]

> OpenCode is a strong base, and with a couple modifications it can become a very effective harness.

I personally didn't find it to be competitve with Claude Code as a harness. Can I ask how you modified it to perform better?

[Aeroi]

I haven’t run formal evals but i improved the experience for my own needs and it feels noticeably better with these modifications.

-Claude-style subagents -an MCP layer for higher-level tools -Cursor-style control plane modes like Ask, Plan, Debug, and Build.

The MCP layer lets the harness use things like GitHub file/code read, PR creation, web search/fetch, structured user questions, plan-mode switching, user skills, and subagents.

So the improvement is mostly from better ui/ux orchestration and tool access. There's some things from hermes that are interesting as well.

Most of my focus has been on applying this stack to sandboxed cloud agents so you can properly code and work from mobile devices.

I can't definitively say that the stack is better or worse than Claude code, more just tuned for my use case I guess.

[eloisant]

What issues do you have with OpenCode?

Personally I use it for the TUI, it's way better than Claude Code's one.

[ryanlitalien]

Kudos! Cool idea, I'm on the same path you are, yet you're just one step ahead. For mouse.dev, what are you using for the cloud agent sandbox piece? I haven't moved my agents to the cloud yet (for on the go mobile enablement). Would Islo be a competitor to mouse?

https://islo.dev/

https://www.incredibuild.com/blog/why-we-built-islo-ai-codin...

[Aeroi]

cool! I've been mostly building for what coding from an iphone can look like. the cloud agent sandbox portion is definitely not polished yet but working well so far. i looked at daytona, e2b, modal ect. but decided to roll my own with fly.io. ttl on agent create. mouse uses per-thread sandboxes (not shared-container multi-workspace) and then post-gres for agent history ect.

i'll have to look more at islo, I definitely think its a growing space with alot of opportunity for those that participate and solve problems.

[ryanlitalien]

Great ideas, I'll look at those too. We're only a few steps away from building our own cloud providers :D.

[adobrawy]

I'm a Claude Code Web fan and a rather heavy user. So I was interested in your product. However, I couldn't find an answer on the website. What parts did you find so good that you ported them?

[Aeroi]

Nothing groundbreaking but i'll do a blog writeup on the architecture if it would be helpful for people. My focus has been on mobile.

The main pieces I've integrated for mouse.dev inspired by claude/cursor was plan mode, agent questions, subagents, pre/post hooks, context compaction, repo-local skills, and permission modes. So mostly tools like enter_plan_mode, ask_user_question, and spawn_subagent, plus .mouse/skills and .mouse/plans.

One nice feature is continuity. If you’re working on desktop and save a plan to .mouse/plans, you can pick it up later on mobile with cloud agents, or do the reverse. You can plan something from your phone, then when you’re back at your desk, review it/build it. That was my initial goal with this project because I've found the plan act loop so helpful.

Mouse Cloud Agents is mostly an OpenCode-based harness, but everything routes through our MCP/event system so it’s mobile-first and provider-agnostic.

I intentionally skipped a lot of IDE and Claude Code style desktop features. The bet is that this new style of coding is becoming less “edit files in an IDE” and more steer a capable coding chatbot.

Would love to hear from anyone reading that's iterating on harness architecture, it's been really fun to work on.