Claude 4.5 Opus

This documentation is valid for the following list of our models:

• anthropic/claude-opus-4-5

• claude-opus-4-5

• claude-opus-4-5-20251101

Try in Playground

As of February 13, 2026, the streaming response format for Anthropic models has changed.

Model Overview

A high-performance chat model that delivers state-of-the-art results on real-world software engineering benchmarks.

How to Make a Call

Create AI/ML API Key

How to make the first API call

1️⃣ Required setup (don’t skip this) ▪ Create an account: Sign up on the AI/ML API website (if you don’t have one yet). ▪ Generate an API key: In your account dashboard, create an API key and make sure it’s enabled in the UI.

2️ Copy the code example At the bottom of this page, pick the snippet for your preferred programming language (Python / Node.js) and copy it into your project.

3️ Update the snippet for your use case ▪ Insert your API key: replace <YOUR_AIMLAPI_KEY> with your real AI/ML API key. ▪ Select a model: set the model field to the model you want to call. ▪ Provide input: fill in the request input field(s) shown in the example (for example, messages for chat/LLM models, or other inputs for image/video/audio models).

4️ (Optional) Tune the request Depending on the model type, you can add optional parameters to control the output (e.g., generation settings, quality, length, etc.). See the API schema below for the full list.

5️ Run your code Run the updated code in your development environment. Response time depends on the model and request size, but simple requests typically return quickly.

If you need a more detailed walkthrough for setting up your development environment and making a request step by step — feel free to use our Quickstart guide.

API Schema

post

Body

application/json

modelstring · enumRequiredPossible values:

stop_sequencesstring[]Optional

Custom text sequences that will cause the model to stop generating.

streambooleanOptional

If set to True, the model response data will be streamed to the client as it is generated using server-sent events.

Default: false

systemstringOptional

A system prompt is a way of providing context and instructions to Claude, such as specifying a particular goal or role.

max_tokensnumberOptional

The maximum number of tokens that can be generated in the chat completion. This value can be used to control costs for text generated via API.

Default: 32000

temperaturenumber · max: 1Optional

Amount of randomness injected into the response. Defaults to 1.0. Ranges from 0.0 to 1.0. Use temperature closer to 0.0 for analytical / multiple choice, and closer to 1.0 for creative and generative tasks. Note that even with temperature of 0.0, the results will not be fully deterministic.

top_pnumber · max: 1Optional

An alternative to sampling with temperature, called nucleus sampling, where the model considers the results of the tokens with top_p probability mass. So 0.1 means only the tokens comprising the top 10% probability mass are considered. We generally recommend altering this or temperature but not both.

top_knumberOptional

Only sample from the top K options for each subsequent token. Used to remove "long tail" low probability responses. Recommended for advanced use cases only. You usually only need to use temperature.

Responses

200Success

application/jsontext/event-stream

idstringRequired

A unique identifier for the chat completion.

Example: chatcmpl-CQ9FPg3osank0dx0k46Z53LTqtXMl

objectstring · enumRequired

The object type.

Example: chat.completionPossible values:

creatednumberRequired

The Unix timestamp (in seconds) of when the chat completion was created.

Example: 1762343744

modelstringRequired

The model used for the chat completion.

Example: anthropic/claude-opus-4-5

post/v1/chat/completions

cURLJavaScriptPython

curl -L \
  --request POST \
  --url 'https://api.aimlapi.com/v1/chat/completions' \
  --header 'Authorization: Bearer <YOUR_AIMLAPI_KEY>' \
  --header 'Content-Type: application/json' \
  --data '{
    "model": "anthropic/claude-opus-4-5",
    "messages": [
      {
        "role": "user",
        "content": "Hello"
      }
    ]
  }'

200Success

{
  "id": "chatcmpl-CQ9FPg3osank0dx0k46Z53LTqtXMl",
  "object": "chat.completion",
  "created": 1762343744,
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "Hello! I'm just a program, so I don't have feelings, but I'm here and ready to help you. How can I assist you today?",
        "refusal": null,
        "annotations": null,
        "audio": null,
        "tool_calls": null
      },
      "finish_reason": "stop",
      "logprobs": null
    }
  ],
  "model": "anthropic/claude-opus-4-5",
  "usage": {
    "prompt_tokens": 137,
    "completion_tokens": 914,
    "total_tokens": 1051,
    "completion_tokens_details": null,
    "prompt_tokens_details": null
  },
  "meta": {
    "usage": {
      "credits_used": 120000,
      "usd_spent": 0.06
    }
  }
}

Code Example #1

Python

import requests
import json  # for getting a structured output with indentation 

response = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={
        # Insert your AIML API Key instead of <YOUR_AIMLAPI_KEY>:
        "Authorization":"Bearer <YOUR_AIMLAPI_KEY>",
        "Content-Type":"application/json"
    },
    json={
        "model":"claude-opus-4-5",
        "messages":[
            {
                "role":"user",
                "content":"Hello"  # insert your prompt here, instead of Hello
            }
        ]
    }
)

data = response.json()
print(json.dumps(data, indent=2, ensure_ascii=False))

JavaScript

Response

{
  "id": "msg_01NxAGYo8VfNu5UAEdmQjv62",
  "object": "chat.completion",
  "model": "claude-opus-4-5-20251101",
  "choices": [
    {
      "index": 0,
      "message": {
        "reasoning_content": "",
        "content": "Hello! How are you doing today? Is there something I can help you with?",
        "role": "assistant"
      },
      "finish_reason": "end_turn",
      "logprobs": null
    }
  ],
  "created": 1764265437,
  "usage": {
    "prompt_tokens": 8,
    "completion_tokens": 20,
    "total_tokens": 28
  },
  "meta": {
    "usage": {
      "tokens_used": 1134
    }
  }
}

Code Example #2: Streaming Mode

As of February 13, 2026, the streaming response format for Anthropic models has changed. Specifically, the usage fields were renamed as follows:

• the state structure is no longer used,

• input_tokens → prompt_tokens,

• output_tokens → completion_tokens,

• a new total_tokens field has been added.

Python

import requests
import json  # for getting a structured output with indentation 

response = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={
        # Insert your AIML API Key instead of <YOUR_AIMLAPI_KEY>:
        "Authorization":"Bearer <YOUR_AIMLAPI_KEY>",
        "Content-Type":"application/json"
    },
    json={
        "model":"anthropic/claude-opus-4-5",
        "messages":[
            {
                "role":"user",
                "content":"Hi! What do you think about mankind?" # insert your prompt
            }
        ]
    }
)

data = response.json()
print(json.dumps(data, indent=2, ensure_ascii=False))

cURL

Response

data: {"id":"msg_01VbjSwQZsZSLXQaPYkufja8","choices":[{"index":0,"delta":{"content":"","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"role":"assistant","content":"","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"Hi","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"! That","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"'s a big","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" question.","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"\n\nI find","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" humans","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" genu","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"inely fascinating—","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"the creativity","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":", the capacity","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" for kind","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"ness and","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" cr","role":"assistant","refusal":null}}],"created":1770995433,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"uelty, the way you","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" build","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" complex","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" societies and art","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" and","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" science","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" while","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" also struggling with problems you","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"'ve","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" understood","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" for centuries. There","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"'s something compelling about a","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" species that can land","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" robots","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" on Mars","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" and also","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" argue","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" about what","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" to","role":"assistant","refusal":null}}],"created":1770995434,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" have for dinner.\n\nI","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" don","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"'t think","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" I'd","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" character","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"ize humanity as simply","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" \"good\" or \"bad.\" People","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" seem","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" capable","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" of remarkable","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" things in","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" both directions,","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" often","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" the","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" same individuals","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" depending","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" on circumstances.","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"\n\nIs","role":"assistant","refusal":null}}],"created":1770995435,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" there a","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" particular angle","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" you","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"'re curious about—","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"history","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":", psychology","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":", where","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" things","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" might","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" be headed","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"?","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" Or","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" just","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" wondering","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" how","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" an","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" AI sees","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":" things?","role":"assistant","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"role":"assistant","content":"","refusal":null}}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}

data: {"id":"","choices":[{"index":0,"delta":{"content":"","role":"assistant","refusal":null},"finish_reason":"stop"}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":{"prompt_tokens":16,"completion_tokens":143,"total_tokens":159}}

data: {"id":"","choices":[{"index":0,"finish_reason":"stop"}],"created":1770995436,"model":"claude-opus-4-5-20251101","object":"chat.completion.chunk","usage":null}