Questions

[null-axiom]

Does it matter which model I use between the build and plan agents?

And what about the historian agent?

Does using the same model between the three have benefits?

I’m curious whether using different models affects things like compaction, memory usage, context handling etc.

[ualtinok]

Magic-context itself is model agnostic so we expect all models to run properly. However the quality of compartments, memory extraction, consolidation all depends on model's capabilities and intelligence. If you're already using a high iq main model like opus/gpt5.4 you can still use a lower historian because historian's output is relatively less crucial (I personally still use gpt-5.4 via github-copilot for historian because github-copilot is request based and however long historian needs to run doesn't change cost for me)

You can always experiment with different models and also check their background outputs via our dashboard by analyzing compartment/memory outputs etc.

[null-axiom]

This may be a bug, but I’ve noticed that whenever I switch between the build and plan agents, if they’re using different models, the usage panel on the right side of the TUI briefly 'shrinks' as though it’s reprocessing something. When both modes use the same model, that flicker does not happen.

My assumption is that this may be configuration-related, possibly because Opencode is re-reading the model settings when switching agents, and the two models may have different context window limits.

To reproduce, it's just to have two different models in build and plan. Then write something in plan agent, switch to build agent say something else and you will see the 'shrink'.

[ualtinok]

That's the normal behaviour, as you expected, when context size is different it should show the usage differently.