Choose the right model

const session = client.createSession({
  model: 'claude-sonnet-4-5-20250929',
});

const session = client.createSession({
  model: 'gpt-5.2',  // Automatically routes to OpenAI
});

const session = client.createSession({
  model: 'or:mistralai/mistral-large',
});

// Or without prefix for unknown models (auto-detected)
const session = client.createSession({
  model: 'deepseek/deepseek-chat',  // Routes to OpenRouter
});

// Anthropic
'claude-sonnet-4-5-20250929'  // → Anthropic
'claude-opus-4-5-20251101'    // → Anthropic

// OpenAI
'gpt-5.2'                     // → OpenAI
'o4-mini'                     // → OpenAI

// OpenRouter (explicit)
'or:mistralai/mistral-large'  // → OpenRouter
'or:google/gemini-pro'        // → OpenRouter

// OpenRouter (auto-detected)
'deepseek/deepseek-chat'      // → OpenRouter (unknown model)
'meta-llama/llama-3-70b'      // → OpenRouter (unknown model)

const session = client.createSession({
  env: {
    ANTHROPIC_MODEL: 'claude-opus-4-5-20251101',
  },
});

const session = client.createSession({
  env: {
    ANTHROPIC_MODEL: 'claude-sonnet-4-5-20250929',
    CLAUDE_CODE_SUBAGENT_MODEL: 'claude-haiku-4-5-20251001',
    ANTHROPIC_DEFAULT_HAIKU_MODEL: 'or:mistralai/devstral-2512:free',
  },
});

mistralai/*           → All Mistral models
meta-llama/*          → All Llama models
deepseek/*            → All DeepSeek models

Endpoint: https://your-openrouter-instance.com/api/v1

{
  "error": {
    "type": "authentication_error",
    "message": "No OpenRouter API key configured for issuer: xxx"
  }
}

{
  "error": {
    "type": "api_error",
    "message": "OpenRouter error: Model not found"
  }
}