Using any cerebras model with api key causes unsupported property errors

[sra]

Description

Using a Cerebras provider connected via /connect or opencode auth login the model list is properly retrieved and you can select one, but when using any model I get:

body.maxTokens: property 'body.maxTokens' is unsupported body.thinking: property 'body.thinking' is unsupported

Errors back

OpenCode version

1.0.223

Steps to reproduce

1. Authorize cerebras via /connect and api key
2. Select any cerebras model
3. type in a prompt
4. (or) opencode run --model cerebras/gpt-oss-120b "test" Error: body.maxTokens: property 'body.maxTokens' is unsupported body.thinking: property 'body.thinking' is unsupported

Screenshot and/or share link

https://opncd.ai/share/W5OP1lFi

Operating System

Darwin Mac 25.2.0

Terminal

Warp

[github-actions[bot]]

This issue might be a duplicate of or related to existing Cerebras provider issues. Please check:

• #1481: Cerebras API Bad Request errors with max_tokens
• #4086: Could not set base URL for Cerebras provider
• #976: Docs for OpenAI Compatible providers like Cerebras

The errors you're experiencing (unsupported properties for maxTokens and thinking) suggest there may be compatibility issues between the Vercel AI SDK and the Cerebras API request format. These related issues might provide context or workarounds.

[sra]

I checked this on dev branch and it doesn't happen so something between v1.0.223 and dev looks to have fixed it. I'll verify in v1.0.224 and close this

[sra]

As of v1.1.1 this is resolved.