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chenxiao5580-cmd
chenxiao5580-cmd

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Use GPT, Claude, and Gemini with the OpenAI SDK - one base_url, any language

#ai #api #javascript #python

If you're juggling separate SDKs and API keys for OpenAI, Anthropic, and Google, here's a simpler setup: point the OpenAI SDK at an OpenAI-compatible gateway and call GPT, Claude, and Gemini through one base_url and one key — at a flat, predictable per-call price instead of three separate per-token bills.

Here's the exact change in five common stacks.

Python (OpenAI SDK) 

from openai import OpenAI

client = OpenAI(
    base_url="https://modelishub.com/v1",
    api_key="YOUR_MODELIS_KEY",
)
resp = client.chat.completions.create(
    model="gpt-4o-mini",
    messages=[{"role": "user", "content": "Hello"}],
)
print(resp.choices[0].message.content)
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The rest of your code stays the same — only base_url and api_key change.

Node.js (openai v4) 

import OpenAI from 'openai';

const client = new OpenAI({
  baseURL: 'https://modelishub.com/v1',
  apiKey: process.env.MODELIS_API_KEY,
});

const resp = await client.chat.completions.create({
  model: 'gpt-4o-mini',
  messages: [{ role: 'user', content: 'Hello' }],
});
console.log(resp.choices[0].message.content);
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curl (works in any language) 

curl https://modelishub.com/v1/chat/completions \
  -H "Authorization: Bearer YOUR_MODELIS_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"gpt-4o-mini","messages":[{"role":"user","content":"Hello"}]}'
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The same pattern works in Go, Java, PHP, Rust — anywhere you can make an HTTP request.

LangChain 

from langchain_openai import ChatOpenAI

llm = ChatOpenAI(
    base_url="https://modelishub.com/v1",
    api_key="YOUR_MODELIS_KEY",
    model="gpt-4o-mini",
)
print(llm.invoke("Hello").content)
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Switching between GPT, Claude, and Gemini

To use a different model, just change the model id — claude-sonnet-4-6, gemini-2.5-flash, and so on. Same endpoint, same key. Fetch the full list any time with GET /v1/models.

resp = client.chat.completions.create(
    model="claude-sonnet-4-6",      # or gemini-2.5-flash, gpt-4o, ...
    messages=[{"role": "user", "content": "Hello"}],
)
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This runs on Modelis, an OpenAI-compatible LLM gateway that auto-routes each request to a model fitted to the task and bills a flat per-call price (not per-token), so your bill stays predictable regardless of which model answered. Free tier to try it — details + free key.

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