LongCat 2.0 and GPT-5.6 Terra are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
LongCat 2.0, from meituan, has a 1,048,756-token context window and is priced at $0.30/M tokens input, $1.20/M tokens output on OpenRouter.
GPT-5.6 Terra, from OpenAI, has a 1,050,000-token context window and is priced at $2/M tokens input, $12/M tokens output on OpenRouter.