Quickstart — Migrating from a Gateway

Already calling the OpenAI API? Migrating to FreeRouter is two edits: change the base URL and swap the key. No SDK changes, no request rewrites.

The two changes

FreeRouter is flexible about the format your client already speaks: it supports the popular API shapes — OpenAI, OpenRouter, Anthropic, and Google — with OpenAI-compatible as the default, so your existing code keeps working with no rewrites. Migrating is two edits: point your client at FreeRouter and use your fr_live_... key (with its shape set to match your client) — and bring your current gateway key with you: paste it into the dashboard under Providers → Add provider, then attach a routing rule that sends traffic to it (the full flow is in Getting Started):

Migration assistant — generate an agent prompt

Switching from another gateway? Use the wizard below to construct a prompt you can paste into your coding agent. The prompt asks the agent to study the FreeRouter docs and your code, then come back with a migration plan for your review — not to start rewriting code.

curl

curl https://api.freerouter.com/v1/chat/completions \
  -H "Authorization: Bearer $FREEROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-4o-mini",
    "messages": [
      { "role": "system", "content": "You are concise." },
      { "role": "user", "content": "Say hi in one word." }
    ]
  }'

Streaming with curl

Set "stream": true to receive server-sent events, exactly like the OpenAI API:

curl https://api.freerouter.com/v1/chat/completions \
  -H "Authorization: Bearer $FREEROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -N \
  -d '{
    "model": "openai/gpt-4o-mini",
    "stream": true,
    "messages": [{ "role": "user", "content": "Count to 3." }]
  }'

Python (openai SDK)

The official openai Python SDK takes a base_url and api_key. Set those two and nothing else changes:

# pip install openai
import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.freerouter.com/v1",
    api_key=os.environ["FREEROUTER_API_KEY"],
)

resp = client.chat.completions.create(
    model="openai/gpt-4o-mini",
    messages=[
        {"role": "user", "content": "Hello from FreeRouter!"},
    ],
)

print(resp.choices[0].message.content)

Streaming in Python

stream = client.chat.completions.create(
    model="openai/gpt-4o-mini",
    messages=[{"role": "user", "content": "Count to 3."}],
    stream=True,
)

for chunk in stream:
    delta = chunk.choices[0].delta.content or ""
    print(delta, end="", flush=True)

Node (openai SDK)

The openai Node SDK is the same story — pass baseURL and apiKey:

// npm install openai
import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://api.freerouter.com/v1",
  apiKey: process.env.FREEROUTER_API_KEY,
});

const resp = await client.chat.completions.create({
  model: "openai/gpt-4o-mini",
  messages: [{ role: "user", content: "Hello from FreeRouter!" }],
});

console.log(resp.choices[0].message.content);

Streaming in Node

const stream = await client.chat.completions.create({
  model: "openai/gpt-4o-mini",
  messages: [{ role: "user", content: "Count to 3." }],
  stream: true,
});

for await (const chunk of stream) {
  process.stdout.write(chunk.choices[0]?.delta?.content ?? "");
}

Choosing a model

Pass a model string in the model field. FreeRouter uses provider/model style identifiers so a request is unambiguous across gateways — for example openai/gpt-4o-mini or anthropic/claude-3.5-sonnet. Your routing rule then decides which gateway actually serves that model. List what's available with the /v1/models endpoint.