Nemotron Nano 9B V2 and GPT-5.1-Codex are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Nemotron Nano 9B V2, from Nvidia, has a 32,000-token context window and is priced by the provider serving it on OpenRouter.
GPT-5.1-Codex, from OpenAI, has a 400,000-token context window and is priced at $1.25/M tokens input, $10/M tokens output on OpenRouter.