Helicon vs OpenCode

At a glance

What each one is

OpenCode is a good answer to a different question: how do I get an open agent loop that I control end to end, across whichever providers I like. That control comes with provider configuration and, for most people, pay as you go API billing.

Helicon does not try to own the loop. Muse Code owns the loop. Helicon is the window: sessions grouped by working directory, resume, inline diffs, an approval queue, and what each thread would have cost at published rates.

Where they actually differ

Subscription reuse is the point

A recurring complaint from people who buy a coding subscription is finding that a favourite harness routes through its own API metering instead. Helicon uses your muse login and nothing else, so the plan you bought is the plan that pays.

Terminal versus window

OpenCode is a terminal experience. Helicon exists because the terminal has no persistent history UI, no cross project triage and no cost surface.

Protocol native

Helicon speaks the Muse Code Session Protocol through Meta's MIT SDK rather than scraping a TUI, so sessions started from the terminal are discovered and resumable.

Choose OpenCode if

• You want to choose and mix providers yourself.
• You are happy in a terminal and want maximum control over the agent loop.
• You need an agent where no vendor CLI is involved.

Choose Helicon if

• Your subscription is Muse Code and you want it to be the thing that pays.
• You want a GUI with history, diffs, approvals and cost.
• You want sessions started in the muse TUI to be visible and resumable.

Can you use both?

They are not exclusive, but they are not complementary either: one is a harness, the other is a client for a different harness. Pick by whether your Muse Code plan should be doing the work.