Claude Opus 4.5 and Text Embedding 3 Small are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Claude Opus 4.5, from Anthropic, has a 200,000-token context window and is priced at $5/M tokens input, $25/M tokens output on OpenRouter.
Text Embedding 3 Small, from OpenAI, has a 8,192-token context window and is priced at $0.02/M tokens on OpenRouter.