Could not use model "Gemini 3 Pro Preview" of Github copilot provider: "invalid request body" #4816

Description

I'm using Github copilot provider's gemini-3 to write code, but it seems it's not able to call any tool, even with a simple "list dir" tool call, the TUI reports error: "invalid request body".
Show as below:

OpenCode version

1.0.119

Steps to reproduce

1. cd into an empty dir
2. run opencode . and switch to copilot's gemini-3 model
3. Send prompt "write a hello world in hello.go"

What I got:

Screenshot and/or share link

https://opencode.ai/s/hXWfg5i2

Operating System

macOS 15.6

Terminal

alacritty