Switching from GPT to Claude in 5 Lines: How an OpenAI-Compatible Gateway Makes Model Swaps Trivial

When your production app calls GPT-4o and Anthropic announces a price drop on Claude, you don't want to refactor your whole codebase.

The trick? Point the OpenAI SDK at a different base URL.

from openai import OpenAI

# Before: direct to OpenAI
client = OpenAI(api_key="sk-...")

# After: one key, any model
client = OpenAI(
    api_key="agent-token-key",
    base_url="https://api.agentoken.co/v1"
)

response = client.chat.completions.create(
    model="claude-3-5-sonnet",  # swap to gpt-4o, gemini-1.5-pro, etc.
    messages=[{"role": "user", "content": "Hello!"}]
)

That's it. Same SDK, same request shape, different model behind the scenes.

Why this matters

Most devs build on OpenAI first because the SDK is the most familiar. When you later want to add Claude for long context or Gemini for free tier, you end up maintaining:

• 3 SDK clients
• 3 auth flows
• 3 billing dashboards
• 3 rate limit handlers

A compatible gateway collapses all of that into one. You change the model string, and the gateway handles routing, retries, and failover.

Try it

Agent Token gives you one key that works across GPT, Claude, Gemini and more, with pay-as-you-go pricing. No per-provider accounts needed — especially useful if you are in SEA where international credit cards are a pain.

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Built for devs who just want to ship, not juggle 5 SDKs.