Error: "this model does not support image input" with paid providers (GitHub Copilot, Anthropic, etc.) but works with free models

[NeuralLabs83]

Description

Steps to reproduce:

1. Use OpenCode with any paid provider (GitHub Copilot, Anthropic direct, etc.)
2. Drag/drop an image into the chat
3. Error: "Cannot read 'image.png' (this model does not support image input)"

Expected behavior:

• Image should be processed correctly (like with free models)

Environment:

• OS: Windows
• Provider used: github-copilot (several models tested: claude-opus-4.6, claude-sonnet-4.5, gpt-5.2)
• Free model that works: big-pickle

Notes:

• Error occurs with ALL paid models tested
• Free models like big-pickle DO accept images
• Error message says model doesn't support images, but that's false for Claude Opus/Sonnet and GPT-5.2 which are multimodal

Plugins

No response

OpenCode version

No response

Steps to reproduce

No response

Screenshot and/or share link

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Operating System

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Terminal

No response

[github-actions]

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

• [Bug] look_at tool cannot read image files - "this model does not support image input" even with vision-capable model #16184: Same error message "this model does not support image input" with vision-capable models
• model "claude-opus-4.6" not supported for vision #14289: Claude Opus 4.6 not supported for vision — same provider/model combination
• Read tool cannot pass image data to vision-capable models #15728: Read tool cannot pass image data to vision-capable models
• [ModelScope] Custom Provider with Qwen Model Cannot Recognize Images - "Image Input Not Supported" #15040: Custom provider with vision-capable model getting "Image Input Not Supported"
• Unable to read images for some models #5359: Unable to read images for some models

If your issue is distinct (e.g., specifically about the paid vs free provider distinction), please add more detail to differentiate it from the above.

[mtomas7]

Please see if this config tip will help: #15728 (comment)