openrouter

client<llm> MyClient {
  provider openrouter
  options {
    model "openai/gpt-4o-mini"
  }
}

OpenRouter-specific options

The openrouter provider extends openai-generic with OpenRouter-specific defaults. See openai-generic for the full list of supported options.

api_key

string

Default: env.OPENROUTER_API_KEY

base_url

string

Default: https://openrouter.ai/api/v1

model

stringRequired

The model to use, in OpenRouter’s provider/model-name format.

Model	Description
`openai/gpt-4o-mini`	Fast, cost-effective
`anthropic/claude-3.5-sonnet`	Claude 3.5 Sonnet
`anthropic/claude-3-haiku`	Fast Claude variant
`google/gemini-2.0-flash-001`	Gemini 2.0 Flash
`meta-llama/llama-3.1-70b-instruct`	Llama 3.1 70B

OpenRouter supports model variants for routing preferences (e.g., :nitro for high-throughput):

BAML

1 client<llm> NitroClient {
2   provider openrouter
3   options {
4     model "meta-llama/llama-3.1-70b-instruct:nitro"
5   }
6 }

For the complete list, see OpenRouter Models.

App attribution headers

OpenRouter supports optional headers for app attribution. Pass these via the headers option:

Header	Description
`X-Title`	Your app name, shown on openrouter.ai rankings
`HTTP-Referer`	Your site URL for rankings and attribution

BAML

1 client<llm> OpenRouterWithAttribution {
2   provider openrouter
3   options {
4     model "anthropic/claude-3-haiku"
5     headers {
6       "X-Title" "My App"
7       "HTTP-Referer" "https://myapp.com"
8     }
9   }
10 }

For all other options (temperature, max_tokens, headers, etc.), see openai-generic and the OpenRouter API documentation.

1	client<llm> MyClient {
2	provider openrouter
3	options {
4	model "openai/gpt-4o-mini"
5	}
6	}

1	client<llm> NitroClient {
2	provider openrouter
3	options {
4	model "meta-llama/llama-3.1-70b-instruct:nitro"
5	}
6	}

1	client<llm> OpenRouterWithAttribution {
2	provider openrouter
3	options {
4	model "anthropic/claude-3-haiku"
5	headers {
6	"X-Title" "My App"
7	"HTTP-Referer" "https://myapp.com"
8	}
9	}
10	}