Muse Spark 1.2 and MiniMax M3 are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Muse Spark 1.2, from Meta, has a 1,048,576-token context window and is priced at $1.25/M tokens input, $4.25/M tokens output on OpenRouter.
MiniMax M3, from MiniMax, has a 1,048,576-token context window and is priced at $0.23/M tokens input, $0.96/M tokens output on OpenRouter.