Claude Opus 5.5

curl

curl https://api.modelrail.cc/v1/chat/completions \
  -H "Authorization: Bearer $MODELRAIL_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"claude-opus-5-5","messages":[{"role":"user","content":"Hello"}]}'

OpenAI SDK

from openai import OpenAI
client = OpenAI(base_url="https://api.modelrail.cc/v1", api_key=KEY)
r = client.chat.completions.create(model="claude-opus-5-5", messages=[{"role":"user","content":"Hello"}])

Anthropic SDK

import anthropic
client = anthropic.Anthropic(base_url="https://api.modelrail.cc", api_key=KEY)
r = client.messages.create(model="claude-opus-5-5", max_tokens=1024, messages=[{"role":"user","content":"Hello"}])