# Claude Opus 4.5

Claude Opus 4.5 is an Opus model that combines deep coding capability with a new effort parameter, giving you explicit control over how much reasoning the model applies to each request.

- **Model ID:** `anthropic/claude-opus-4.5`
- **Type:** chat
- **Providers:** anthropic, bedrock, vertexAnthropic
- **Context window:** 200,000
- **Maximum output tokens:** 64,000
- **Pricing:** $5/1M input tokens, $25/1M output tokens
- **Canonical page:** https://vercel.com/ai-gateway/models/claude-opus-4.5

## Supported parameters

Detailed capability metadata has not been reported for this model.

## Example

```ts
import { streamText } from 'ai'

const result = streamText({
  model: 'anthropic/claude-opus-4.5',
  prompt: 'Why is the sky blue?'
})
```

## About

Claude Opus 4.5 became available on AI Gateway on November 24, 2025. The model adds a new `effort` parameter that affects all token types and governs how much token usage the model applies per request. It defaults to high and operates independently of the thinking budget, giving you a separate lever for token efficiency without adjusting extended thinking configuration.

Difficult coding tasks and agentic workflows are core strengths, especially those combining computer use and tool use. Claude Opus 4.5 handles context from external memory files effectively. Frontend coding and design for real-world web applications are established strengths of this checkpoint.

To use Claude Opus 4.5, set the model to `anthropic/claude-opus-4.5` and configure `effort` through `providerOptions` in the AI SDK, Chat Completions API, Responses API, Messages API, or other API formats. The effort setting is independent of the thinking budget. Set both separately to manage the cost-quality tradeoff for different request types in the same application.

Anthropic designed Claude Opus 4.5 for the demanding end of the agent capability spectrum: workflows involving computer use, external tool calls, memory file management, and frontend development where design quality and code correctness both apply.

## What to consider

The `effort` parameter (high by default) affects all token types for a request. Set it in `providerOptions.anthropic.effort` to manage token usage per request when running mixed workloads with varying complexity.

## When to use

### Best For

- **Agentic workflows combining computer use and tool use**, highlighted as a core strength for tasks requiring both capabilities in combination
- **Frontend coding and design for real-world web apps** that need production-quality output on complex UI development tasks
- **Demanding reasoning and complex problem solving** where Opus-depth analysis is required
- **External memory file handling.** The model excels at managing context across long agentic sessions with memory file access
- **Tasks where effort-level control matters**, such as workloads mixing simple and complex requests that benefit from per-request token usage management

### Consider Alternatives When

- You need the fastest possible response for interactive use. Haiku 4.5 or Sonnet 4 variants are better suited
- The task doesn't require Opus-level depth and a Sonnet model handles it equivalently at lower cost
- You need the 1M token context window, which came to Opus models with version 4.6

## Best for

- **Agentic workflows combining computer use and tool use:** A core strength for tasks requiring both capabilities in combination
- **Frontend coding and design:** Production-quality output on complex UI development tasks for real-world web apps
- **Demanding reasoning and complex problem solving:** The `effort` parameter (high by default) applies maximum token usage per request for hard analytical work
- **External memory file handling:** The model manages context across long agentic sessions with memory file access
- **Effort-level control:** Workloads mixing simple and complex requests benefit from per-request token usage management

## Consider alternatives

- **Fastest interactive response:** Haiku 4.5 or Sonnet 4 variants suit low-latency use
- **Sonnet-level depth suffices:** A Sonnet model handles tasks that don't require Opus-level reasoning at lower cost
- **1M token context window:** Context size came to Opus models with version 4.6

## Frequently asked questions

### What is the effort parameter in Claude Opus 4.5 and how does it work?

The effort parameter controls how much token usage the model applies when responding to a request. It defaults to high, affects all token types, and is set independently of the thinking budget via `providerOptions.anthropic.effort` in the AI SDK.

### How do I configure the effort parameter through AI Gateway?

Under `providerOptions.anthropic` in your AI SDK v5 call, pass an `effort` level of `low`, `medium`, or `high` alongside the model string `anthropic/claude-opus-4.5`.

### What agentic capabilities does Opus 4.5 excel at specifically?

Difficult coding tasks, agentic workflows combining computer use and tool use, and complex multi-step problem solving. The model handles tasks requiring sustained reasoning across long contexts and multi-turn interactions.

### How does effort differ from the thinking budget?

They are independent parameters. The effort parameter controls overall token usage across all token types; the thinking budget specifically controls extended reasoning tokens. You can set both separately to tune the cost-quality tradeoff.

### What vision improvements does Opus 4.5 include?

Opus 4.5 includes improvements in general intelligence and visual reasoning, handling image analysis, diagram interpretation, and document understanding with stronger accuracy than previous Opus versions.

### Does Opus 4.5 support the 1M token context window?

No. The 1M token context window came to Opus models with Claude Opus 4.6.

### Is Claude Opus 4.5 suitable for frontend web development work?

Yes, frontend coding and design for developing real-world web applications is specifically listed as an established strength of this model.

## Links

- [Model page](https://vercel.com/ai-gateway/models/claude-opus-4.5)
- [AI Gateway documentation](https://vercel.com/docs/ai-gateway)
- [Provider model documentation](https://docs.anthropic.com/claude/docs/models-overview)
- [Provider pricing](https://www.anthropic.com/pricing#anthropic-api)


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