Seed 2.1 Turbo and Llama 4 Maverick are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Seed 2.1 Turbo, from bytedance-seed, has a 262,144-token context window and is priced at $0.50/M tokens input, $2.50/M tokens output on OpenRouter.
Llama 4 Maverick, from Meta Llama, has a 1,048,576-token context window and is priced at $0.20/M tokens input, $0.696/M tokens output on OpenRouter.