AnthropicFastUltra

Claude Sonnet 4.6

The successor to Claude Sonnet 4.5. Anthropic's frontier Sonnet-tier model for complex reasoning, nuanced understanding, and coding tasks with exceptional instruction following, at the same token pricing as Sonnet 4.5.

5,574/27,870credits

input / output · per 1M tokens

200K context window

16K max output tokens

Vision capabilities

Computer use

Superior code generation

Exceptional instruction following

Prompt caching — cache writes ≈6,967.5 credits per 1M tokens ($3.75), cache reads 557.4 credits per 1M tokens

Server-side web search — 18.58 credits per request

Run it right now

Test this model instantly in the Console Playground — no code required

Use with AI Assistant

Copy usage instructions for Claude, ChatGPT, or other AI

llms.txtllms.txt ↗

Model Specifications

Context Window

200K

tokens

Max Output

16K

tokens

Training Cutoff

2025-04

Compatible SDK

Anthropic

Capabilities

Vision

Function Calling

Streaming

JSON Mode

System Prompt

Token Pricing (per 1M tokens)

Token Type	Credits	USD Equivalent
Input Tokens	5,574	$3.72
Output Tokens	27,870	$18.58
Cached Tokens	557.4	$0.37

* 1,500 credits ≈ $1 (actual charges may vary based on usage)

Quick Start

curl -X POST "https://api.core.today/llm/anthropic/v1/messages" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer cdt_your_api_key" \
  -d '{
  "model": "claude-sonnet-4-6",
  "max_tokens": 4000,
  "system": "You are an expert analyst. Provide detailed, structured analysis.",
  "messages": [
    {
      "role": "user",
      "content": "Analyze the key themes and implications of this research paper: [paper text]"
    }
  ]
}'

Parameters

Parameter	Type	Required	Default	Description
`messages`	array	Yes	-	Array of message objects with role and content
`model`	string	Yes	claude-sonnet-4-6	Model identifier
`max_tokens`	integer	Yes	-	Maximum tokens in response (required, up to 16384)
`system`	string	No	-	System prompt for setting behavior
`temperature`	float	No	1.0	Sampling temperature (0-1)
`stream`	boolean	No	false	Enable streaming responses
`tools`	array	No	-	List of tools the model can use

Examples

Document Analysis

Analyze complex documents

curl -X POST "https://api.core.today/llm/anthropic/v1/messages" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer cdt_your_api_key" \
  -d '{
  "model": "claude-sonnet-4-6",
  "max_tokens": 4000,
  "system": "You are an expert analyst. Provide detailed, structured analysis.",
  "messages": [
    {
      "role": "user",
      "content": "Analyze the key themes and implications of this research paper: [paper text]"
    }
  ]
}'

Code Generation

Generate production-quality code

curl -X POST "https://api.core.today/llm/anthropic/v1/messages" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer cdt_your_api_key" \
  -d '{
  "model": "claude-sonnet-4-6",
  "max_tokens": 4000,
  "messages": [
    {
      "role": "user",
      "content": "Create a TypeScript React component for a data table with sorting, filtering, and pagination. Use modern best practices."
    }
  ],
  "temperature": 0.3
}'

Tool Use

Use tools/functions with Claude

curl -X POST "https://api.core.today/llm/anthropic/v1/messages" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer cdt_your_api_key" \
  -d '{
  "model": "claude-sonnet-4-6",
  "max_tokens": 1000,
  "messages": [
    {
      "role": "user",
      "content": "Look up the current stock price of Apple."
    }
  ],
  "tools": [
    {
      "name": "get_stock_price",
      "description": "Get the current stock price for a given symbol",
      "input_schema": {
        "type": "object",
        "properties": {
          "symbol": {
            "type": "string",
            "description": "Stock ticker symbol"
          }
        },
        "required": [
          "symbol"
        ]
      }
    }
  ]
}'