DeepSeek V4 Pro via OpenRouter incorrectly reports "Key limit exceeded (total limit)"

[IzAlv]

Description

I'm using OpenCode Desktop v1.17.13 on macOS with OpenRouter.

My OpenRouter account has available credit (~$35), and the API key has remaining spending limit.

What works

• Gemini 3.5 Flash via OpenRouter ✅
• DeepSeek V4 Flash via OpenRouter ✅
• Direct OpenRouter API call to deepseek/deepseek-v4-pro using the same API key ✅

What fails

• DeepSeek V4 Pro in OpenCode ❌

OpenCode immediately returns:

Key limit exceeded (total limit)

Verification

I verified that this is not an OpenRouter or API key issue by sending the following request directly to the OpenRouter API:

curl https://openrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer <API_KEY>" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "deepseek/deepseek-v4-pro",
    "messages":[{"role":"user","content":"Reply with exactly: OK"}],
    "max_tokens":10
  }'

The request succeeds and returns:

• model: deepseek/deepseek-v4-pro-20260423
• provider: SiliconFlow
• response: OK

This suggests the problem is specific to OpenCode's handling of DeepSeek V4 Pro rather than OpenRouter or the API key.

Please let me know if I can provide additional logs or help test a fix.

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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