Claude Opus 5 (Fast) and Hy4 preview are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Claude Opus 5 (Fast), from Anthropic, has a 1,000,000-token context window and is priced at $10/M tokens input, $50/M tokens output on OpenRouter.
Hy4 preview, from tencent, has a 1,048,576-token context window and is priced at $0.834/M tokens input, $2.501/M tokens output on OpenRouter.