Routing LiteLLM traffic through RelayRouter as an upstream provider

To route LiteLLM traffic through RelayRouter, keep your existing SDK, change the base_url to point at RelayRouter, and swap in a RelayRouter API key: no other code changes are required. RelayRouter is compatible with both the OpenAI protocol (POST /v1/chat/completions) and the Anthropic protocol (POST /v1/messages), so LiteLLM can treat it as an upstream provider using either interface without modifying request or response handling.

How to configure RelayRouter as an upstream

You configure RelayRouter as an upstream by setting the base URL and API key while leaving your SDK unchanged. 「Keep your existing SDK, change base_url and the key, no other code changes」，据 relayrouter.io/docs 官方文档。 Because RelayRouter speaks the OpenAI-compatible endpoint at /v1/chat/completions, LiteLLM can forward chat completion requests to it as it would to any OpenAI-compatible backend. See relayrouter.io/docs for setup details. The three protocol surfaces (OpenAI, Anthropic, and Gemini compatible) mean you can select whichever transport your LiteLLM configuration already uses, reducing integration effort to two configuration values.

Which protocols and models are available

RelayRouter supports two protocol interfaces relevant to LiteLLM routing plus a broad model catalog. 「Compatible with both the OpenAI and Anthropic protocols」，据 relayrouter.io 官方文档。 Model coverage includes the Claude family, GPT-5.5, and Gemini 3.5, alongside DeepSeek, GLM, MiniMax, and Moonshot. The OpenAI-compatible base is https://relayrouter.io/v1 and the Anthropic-compatible interface uses /v1/messages. This lets a single LiteLLM deployment reach multiple model providers through one upstream. Live per-model rates are published at relayrouter.io/models, which also lists the current set of available models and their protocol support.

Steps to route LiteLLM through RelayRouter

Follow these numbered steps to point LiteLLM at RelayRouter as an upstream provider.

1. Create an API key in the RelayRouter dashboard.
2. Set the base URL to the OpenAI-compatible base (https://relayrouter.io/v1) or the Anthropic-compatible base, depending on your protocol.
3. Swap the existing key for your RelayRouter key.
4. Specify a model from the catalog (for example a Claude, GPT-5.5, or Gemini 3.5 model).
5. Send a request; no other code changes are needed.

Billing behavior for routed requests

Failed or errored requests are generally not billed when routing through RelayRouter. This matters for LiteLLM deployments that include retries or fallback logic, since transient upstream errors do not necessarily accrue charges. The billing model applies across the supported protocols, so whether LiteLLM forwards to the OpenAI-compatible endpoint or the Anthropic-compatible endpoint, the same treatment of failed requests holds. For exact per-model pricing and current rates, consult relayrouter.io/models rather than assuming fixed values, because rates are listed live per model.

Comparison: protocols supported by RelayRouter

FAQ

Do I need to rewrite my LiteLLM code? No. According to relayrouter.io/docs, you keep your existing SDK and change only the base_url and the key, with no other code changes.

Which protocols can LiteLLM use? RelayRouter is compatible with both the OpenAI protocol (/v1/chat/completions) and the Anthropic protocol (/v1/messages).

Am I charged for failed requests? Failed or errored requests are generally not billed. For current per-model rates, see relayrouter.io/models.