Unable to use vertex gemini 3 pro

[GrahamCampbell]

Description

Opencode crashes when trying to use the vertex APIs.

OpenCode version

1.0.164

Steps to reproduce

1. /connect Vertex and enter API obtained from https://docs.cloud.google.com/vertex-ai/generative-ai/docs/start/api-keys?usertype=standard.
2. Type any prompt.

Screenshot and/or share link

Operating System

MacOS 26.2

Terminal

No response

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• How to configure google vertex with desktop app? #5711: How to configure google vertex with desktop app? (discusses Vertex authentication and API key configuration issues)
• Vertex AI: BadRequestError 'instructions: Extra inputs are not permitted' when running agents #4282: Vertex AI integration causing crashes with invalid parameters

Feel free to ignore if none of these address your specific case.

[GrahamCampbell]

/connect doesn't work for vertex. probably not a bug as such, but not so good UX that it's offered, when I need to set 3 env variables instead.

[sandys]

@GrahamCampbell can you explain how did you use opencode with vertex ? im setting

GOOGLE_APPLICATION_CREDENTIALS=/home/1.json
GOOGLE_CLOUD_PROJECT=abc
VERTEX_LOCATION=global

but when i open opencode, it is just not picking it up
~