LLM API

Claude Opus 5 · API guide

Integrate claude-opus-5 through claude. Request examples, parameters, authentication and result handling.

POST/v1/messagesMODELclaude-opus-5

Official reference claude-opus-5Checked 2026-09-27Official docs

Code examples & responses

Request & responseExamples

POST/v1/messages

Server-side request

curl "https://newrouters.com/v1/messages" \
  -H "Content-Type: application/json" \
  -H "x-api-key: $API_KEY" \
  -H "anthropic-version: 2023-06-01" \
  --data '{
  "model": "claude-opus-5",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": "Explain how an HTTP request works in three concise steps."
    }
  ],
  "stream": false
}'

Server-side request

const apiBaseUrl = "https://newrouters.com";
const apiKey = process.env.API_KEY;
if (!apiKey) throw new Error("Set API_KEY in your server environment");

const response = await fetch(apiBaseUrl + "/v1/messages", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "x-api-key": apiKey,
    "anthropic-version": "2023-06-01"
  },
  body: JSON.stringify({
  "model": "claude-opus-5",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": "Explain how an HTTP request works in three concise steps."
    }
  ],
  "stream": false
})
});

const result = await response.json();
if (!response.ok) throw new Error(JSON.stringify(result));
console.log(result);

Server-side request

import json
import os
from urllib.request import Request, urlopen

api_base_url = "https://newrouters.com"
api_key = os.environ["API_KEY"]
body = json.loads("{\"model\":\"claude-opus-5\",\"max_tokens\":1024,\"messages\":[{\"role\":\"user\",\"content\":\"Explain how an HTTP request works in three concise steps.\"}],\"stream\":false}")

request = Request(
    api_base_url + "/v1/messages",
    data=json.dumps(body).encode("utf-8"),
    headers={
    "Content-Type": "application/json",
    "x-api-key": api_key,
    "anthropic-version": "2023-06-01"
    },
    method="POST",
)
with urlopen(request) as response:
    print(json.load(response))

The API origin is filled in. Set API_KEY before running. Examples never submit automatically.

ResponseSelected fields · illustrative values

200Successful result

JSON

{
  "content": [
    {
      "type": "text",
      "text": "..."
    }
  ],
  "stop_reason": "end_turn"
}

Integration flowAnthropic · Native protocol

Prepare a request01
API key + model ID
Use the model’s native protocol and authentication.
SDK / HTTP
Call the native API02
POST /v1/messages
Submit the request structure documented on this page.
Anthropic
Read the response03
content[]
JSON returns a complete result; read SSE increments using native event formats.
JSON / SSE

Use the exact API model ID claude-opus-5. This guide describes the platform contract; check the live catalog before calling the model.

Request example

The platform origin is filled in at build time. Set API_KEY to your server-side key before running.

curl "https://newrouters.com/v1/messages" \
  -H "Content-Type: application/json" \
  -H "x-api-key: $API_KEY" \
  -H "anthropic-version: 2023-06-01" \
  --data '{
  "model": "claude-opus-5",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": "Explain how an HTTP request works in three concise steps."
    }
  ],
  "stream": false
}'

Protocol and response

This model uses the claude protocol. Read its native response and usage fields; do not wrap the request in the media task input envelope.

Supported endpoint templates：

POST /v1/messages
POST /v1/messages/count_tokens

Limit	Catalog value
Context tokens	1000000
Maximum output tokens	128000

For streaming, use the native protocol streaming option and parse its events; check supported capabilities in the live catalog.

Official sources and identity

Checked: 2026-09-27 · Platform model: claude-opus-5 · Official reference: claude-opus-5

Pricing and troubleshooting

Check current availability, contract and account pricing before integration. Keep request IDs and usage receipts when diagnosing errors. Complete API reference