Ox Alpha and Phi 4 are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Ox Alpha, from Stealth, has a 1,048,576-token context window and is free to use on OpenRouter.
Phi 4, from Microsoft, has a 16,384-token context window and is priced at $0.07/M tokens input, $0.14/M tokens output on OpenRouter.