- The default model when
Agenthas nomodelset - The default
OpenAIEmbedderused by many vector database implementations
PgVector creates an OpenAIEmbedder when embedder is omitted. UpstashVectorDb uses Upstash hosted embeddings instead.
Quick fix: Configure a Different Model
Specify the model explicitly. Without one, the agent defaults toOpenAIResponses with gpt-5.4, which requires OPENAI_API_KEY.
For example, to use Google’s Gemini instead of OpenAI:
Quick fix: Configure the Vector Database Embedder
If your vector database defaults toOpenAIEmbedder, pass a different embedder explicitly.
For example, to use Google’s Gemini as an embedder, use GeminiEmbedder: