Claude Opus 4.5

Claude Opus 4.5 is Anthropic’s frontier reasoning model optimized for complex software engineering, agentic workflows, and long-horizon computer use. It offers strong multimodal capabilities, competitive performance across real-world coding and reasoning benchmarks, and improved robustness to prompt injection. The model is designed to operate efficiently across varied effort levels, enabling developers to trade off speed, depth, and token usage depending on task requirements. Opus 4.5 supports advanced tool use, extended context management, and coordinated multi-agent setups, making it well-suited for autonomous research, debugging, multi-step planning, and spreadsheet/browser manipulation. It delivers substantial gains in structured reasoning, execution reliability, and alignment compared to prior Opus generations, while reducing token overhead and improving performance on long-running tasks.

ChatAnthropic200k tokens$5.4503 / $27.2515 · 1M

anthropic/claude-opus-4.5

Context
200k tokens
Completion cap
64,000
Tools
Yes
JSON
Yes
Released
2025-11-24

Call it from Geek Hub

Same OpenAI SDK. Change the base URL and the model id.

curl https://api.geekhub.mx/v1/chat/completions \
  -H "Authorization: Bearer $GEEKHUB_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "anthropic/claude-opus-4.5",
    "messages": [{"role": "user", "content": "Hola"}]
  }'
Get an API key

Frequently asked questions

What is Claude Opus 4.5?
Claude Opus 4.5 is Anthropic’s frontier reasoning model optimized for complex software engineering, agentic workflows, and long-horizon computer use. It offers strong multimodal capabilities, competitive performance across real-world coding and reasoning benchmarks, and improved robustness to prompt injection. The model is designed to operate efficiently across varied effort levels, enabling developers to trade off speed, depth, and token usage depending on task requirements. Opus 4.5 supports advanced tool use, extended context management, and coordinated multi-agent setups, making it well-suited for autonomous research, debugging, multi-step planning, and spreadsheet/browser manipulation. It delivers substantial gains in structured reasoning, execution reliability, and alignment compared to prior Opus generations, while reducing token overhead and improving performance on long-running tasks. Claude Opus 4.5 runs on the Geek Hub API (OpenAI-compatible). Model id: anthropic/claude-opus-4.5.
Is Claude Opus 4.5 free?
No. Input is $5.4503 per 1M tokens and output is $27.2515 per 1M tokens on Geek Hub (markup included).
What is the context length of Claude Opus 4.5?
Claude Opus 4.5 has a 200k tokens context window. It supports up to 64,000 completion tokens.
Does Claude Opus 4.5 support tool calling and structured outputs?
Claude Opus 4.5 accepts tools and tool_choice for function calling. It also supports structured outputs via a JSON schema in response_format.
When was Claude Opus 4.5 released?
Claude Opus 4.5 was released on 2025-11-24.

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