n8n
n8n's OpenAI credential takes a custom base URL. Set it once, and the AI Agent, Basic LLM Chain and other nodes can use NezhaGate models.
1. Create an OpenAI credential
- Credentials → Add credential → OpenAI.
- Enter your NezhaGate key in API Key and
https://nezhagate.com/v1in Base URL; leave Organization ID empty. - Save. n8n reads the model list once to test the connection; that is not billed.
Base URL
https://nezhagate.com/v12. Pick the model in the OpenAI Chat Model node
- Model → From List lists every NezhaGate model, so pick a chat model; or choose ID and type one, such as
gpt-5.5. - Use Responses API is on by default and sends requests to
/v1/responses, where NezhaGate serves the GPT models only. Switch it off for any other model; for GPT models either setting works. - Keep Built-in Tools (Web Search, File Search, Code Interpreter) off; they are OpenAI-hosted features.
- The OpenAI app node's Message a Model always uses
/v1/responses, so it works with GPT models only; use the OpenAI Chat Model node for the others.
Claude (optional)
Create an Anthropic credential with https://nezhagate.com/anthropic in Base URL and the same API key, then pick a Claude model in the Anthropic Chat Model node.
Test
Build a Chat Trigger → AI Agent → OpenAI Chat Model workflow, click Open chat and send a message.
Troubleshooting
The credential test fails
404 means the base URL lacks /v1 or is wrong (it should be https://nezhagate.com/v1); 401 means the key is wrong.
A model returns 400, 404 or 503
Most likely Use Responses API is on with a non-GPT model. Switch it off.
The agent does not call tools, or JSON output has no effect
Not every model supports tool calls or JSON output; pick one that does (see each model's API doc).
