---
title: "anthropic()"
description: "Create an Anthropic Claude language model"
---

Factory function to create an Anthropic Claude model instance.

## Signature

```python
def anthropic(model_id: str) -> LanguageModel
```

## Parameters

<ParamField path="model_id" type="str" required>
  The Anthropic model identifier.
</ParamField>

## Returns

A `LanguageModel` instance configured for Anthropic.

## Environment

Requires `ANTHROPIC_API_KEY` environment variable.

```bash
export ANTHROPIC_API_KEY="sk-ant-..."
```

## Available Models

| Model ID | Description |
|----------|-------------|
| `claude-4-5-opus-20251101` | Claude 4.5 Opus - most capable |
| `claude-4-5-sonnet-20250929` | Claude 4.5 Sonnet - powerful with Thinking mode |
| `claude-4-5-haiku-20251001` | Claude 4.5 Haiku - fast and efficient |
| `claude-4-opus-20250514` | Claude 4 Opus - high capability |
| `claude-4-sonnet-20250514` | Claude 4 Sonnet - balanced |
| `claude-3-5-sonnet-latest` | Claude 3.5 Sonnet - reliable |
| `claude-3-5-haiku-latest` | Claude 3.5 Haiku - fastest |

## Example

```python
from ai_query import generate_text, anthropic

result = await generate_text(
    model=anthropic("claude-4-5-sonnet-20250929"),
    prompt="Hello, world!"
)
```

## Provider Options

```python
result = await generate_text(
    model=anthropic("claude-4-5-sonnet-20250929"),
    prompt="Be creative.",
    provider_options={
        "anthropic": {
            "temperature": 0.7,
            "max_tokens": 2000,
            "top_p": 0.9
        }
    }
)
```
