Anthropic-to-OpenAI schema translation #27047

Description

Description

There is a server-side translation error when using the opencode.ai proxy with tool-enabled clients like Claude Code when targeting DeepSeek models. The proxy fails to correctly nest the tool name within the function object required by the OpenAI/DeepSeek schema.

Error Message

API Error: 400 Error from provider (DeepSeek): Failed to deserialize the JSON body into the target type: tools[0].function: missing field 'name'

Technical Details

When Claude Code sends tool definitions in Anthropic format, the proxy translates them to the OpenAI format. Currently, it appears the proxy is placing the name field at the top level of the tool instead of inside the function wrapper.

Current (Buggy) Translation:
{
"type": "function",
"name": "read_file",
"function": { "description": "...", "parameters": {...} }
}

Expected OpenAI Format:
{
"type": "function",
"function": {
"name": "read_file",
"description": "...",
"parameters": {...}
}
}

Environment

• Client: Claude Code (CLI)
• Model: deepseek-v4-flash-free
• Endpoint: api.opencode.ai/v1

Plugins

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OpenCode version

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Steps to reproduce

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Screenshot and/or share link

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Operating System

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Terminal

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