A Anthropic API alternative with one key for 50+ models

What is Anthropic?

Anthropic provides its Claude models through the Claude API (the Anthropic API), with its own SDKs and Messages API format.

What developers use it for

• Long-document analysis and writing with Claude
• Coding assistants and agents
• Teams that want Claude specifically

Things to consider

• The native Messages API differs from the OpenAI chat format, so switching providers usually means code changes.
• Only Claude models are available on the Anthropic API.

Where Somnus fits

Through Somnus you call Claude models with the OpenAI-style chat format, alongside other makers' models, from the same key.

Every Somnus top-up is credited at 2× or more, and usage is billed at each model's list price, so a dollar of credit buys at least two dollars of usage.

Calling Somnus with the OpenAI SDK

from openai import OpenAI
import os

client = OpenAI(
    api_key=os.environ["SOMNUS_API_KEY"],
    base_url="https://gateway-production-c837.up.railway.app/v1",
)

resp = client.chat.completions.create(
    model="claude-sonnet-5",
    messages=[
      {"role": "user", "content": "Hello"}
    ],
)
print(resp.choices[0].message.content)

Somnus uses the OpenAI chat-completions format, so you use the openai package instead of a provider-specific SDK.

Questions

Related