OptionalapiOptionalbaseOptionaldimensionsOpenAI-format only: request this many dimensions (text-embedding-3-*).
OptionalfetchOptionalheadersOptionalproviderDefault: from the model id (text-embedding-3-small → openai, text-embedding-004 → gemini, nomic-embed-text → ollama), else openai.
OptionalsignalOptionaltimeout
Origin, e.g.
https://api.groq.com/openai/v1for an OpenAI-format host.