Configure n8n's OpenAI credential and model endpoint
n8n is the workflow automation platform where AI steps meet real business processes — and every AI Agent or OpenAI node bills through whatever credential you plug in. n8n's OpenAI credential ships with a Base URL field that accepts any OpenAI-compatible endpoint: point it at Router One and one credential covers GPT, Claude, Gemini, and Grok family models. n8n orchestrates the workflow; the gateway meters it — every step's model call lands in one ledger, and a per-key maxSpend cap keeps a scheduled workflow from silently overrunning its budget.
Configure n8n to use the Router One base URL
In n8n, open Credentials → Add credential → OpenAI (or create one from the credential dropdown on any OpenAI or AI Agent node) and override the Base URL field — it defaults to api.openai.com and accepts any OpenAI-compatible endpoint:
# n8n → Credentials → Add credential → OpenAI API Key: sk-your-router-one-key Base URL: https://api.router.one/v1 # Organization ID: leave blank # In the node: select this credential, set Model to <model-id-from-/models>
Which model ID should n8n send?
Copy the exact model ID from /models, preserving case, hyphens, and version suffixes; do not substitute a display name. Open its detail page and match the supported API endpoints, context window, and capabilities such as tool calling to the provider and features selected in n8n. A catalog listing does not mean the client can use every feature of that model. Give each tool a dedicated API key with a maxSpend cap.
Which API protocol is n8n using?
OpenAI-compatible describes an interface format; it does not make Chat Completions (/v1/chat/completions), Responses (/v1/responses), and Anthropic Messages (/v1/messages) interchangeable. Check the installed client version, provider configuration, and actual request path against the model detail page and API compatibility fact sheet. A successful plain-text chat does not establish support for hosted tools, conversation state, or file-editing features.
Verify the n8n call in your request trace
Send a simple text request from n8n, then match its trace in Dashboard → Logs by time, model, and request_id: tokens, cost, latency, and status. Next, test streaming, tool calls, and multi-turn history separately. For failures, retain the actual request path, full error message, and request_id. If there is no matching log, check client configuration and connectivity before attributing the error to the gateway or upstream.
FAQ
Which n8n nodes pick up this credential?
Nodes using the OpenAI credential type can reuse it, including OpenAI and OpenAI Chat Model. Check each node's selected operation and actual API path: a text-generation request, a Responses request, and a file operation have different compatibility requirements. A shared base URL and key do not establish that every node operation is supported.
Which models can n8n use through the gateway?
Choose a current catalog model that supports both the endpoint and the features n8n uses. Check /models and the model detail page for the exact ID, current rates, and capabilities; a family name such as GPT or Claude is not a compatibility guarantee. Seeing a model in the picker confirms discovery, so verify an actual request too.
Models are listed, but requests fail with 400 or 404. What should I check?
Record the actual request path and error message, then check the exact model ID. A 400 can indicate invalid parameters, unsupported tools, or a model/endpoint mismatch; a 404 can indicate an incorrect path or missing resource, so it does not by itself establish that a model was retired. If the error says must be called via, use the named endpoint or select a model supported on the current endpoint. Do not add or remove /v1 or /chat/completions across all clients indiscriminately.
Does this work from Mainland China?
Yes. The gateway is reachable from Mainland China without a VPN, and the configuration is identical to the global setup.
How do I debug a 401/402/403/429?
Match the request and error message in Dashboard → Logs. For 401, check whether the key was sent and is valid; for 402, check wallet balance and maxSpend; for 403, check key permissions and access restrictions. For 429, distinguish request/token limits from upstream throttling using the error details. Keep the request_id and follow the error-codes reference.