Claude Sonnet 4.5 and Voxtral Small 24B 2507 are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Claude Sonnet 4.5, from Anthropic, has a 1,000,000-token context window and is priced at $3/M tokens input, $15/M tokens output on OpenRouter.
Voxtral Small 24B 2507, from Mistral AI, has a 32,000-token context window and is priced at $0.10/M tokens input, $0.30/M tokens output on OpenRouter.