> ## Documentation Index
> Fetch the complete documentation index at: https://docs.anotherwrapper.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Anthropic

> Set up Anthropic & understand how it's used throughout the app

Anthropic's Claude models are known for strong reasoning, long-context handling, and thoughtful responses. If you want to offer your users a premium chat experience alongside OpenAI, Anthropic is a great pick.

## Get your API key

<Steps>
  <Step title="Create or sign into your Anthropic account">
    Head to the [Anthropic Console](https://console.anthropic.com/dashboard) and sign up or log in.
  </Step>

  <Step title="Generate an API key">
    Go to the [API keys page](https://console.anthropic.com/settings/keys) and click **Create API key**.
  </Step>

  <Step title="Add it to your env">
    Paste the key in your `.env.local` file:

    ```env theme={null}
    ANTHROPIC_API_KEY=your_anthropic_api_key
    ```
  </Step>
</Steps>

<Warning>
  Save your API key right away -- you won't be able to see it again after creation.
</Warning>

## Available models

All models are defined in the unified model registry at `lib/ai/models.ts`. Every Anthropic model supports vision and internet access.

| Model             | ID                  | Features                             |
| ----------------- | ------------------- | ------------------------------------ |
| Claude Opus 4.5   | `claude-opus-4-5`   | Vision, Internet                     |
| Claude Sonnet 4.5 | `claude-sonnet-4-5` | Vision, Internet, Thinking/Reasoning |
| Claude Haiku 4.5  | `claude-haiku-4-5`  | Vision, Internet                     |

<Tip>
  Claude Sonnet 4.5 supports **thinking/reasoning mode** -- the model shows its chain of thought before giving you a final answer. Great for complex tasks where you want transparency.
</Tip>

## Apps using Anthropic

Anthropic is integrated through Vercel AI SDK 6.0, with provider routing handled by `lib/ai/ai-utils.ts`.

<CardGroup cols={2}>
  <Card title="Chat" icon="comments" href="/apps/chat">
    Multi-provider chat app -- Anthropic is available as an LLM provider
  </Card>

  <Card title="Marketing Plan" icon="chart-line" href="/apps/marketing-plan">
    Generate structured marketing plans using Claude models
  </Card>

  <Card title="Launch Simulator" icon="sparkles" href="/apps/launch-simulator">
    Generate Product Hunt launch simulations using Claude models
  </Card>
</CardGroup>

## How it works

The codebase uses Vercel AI SDK 6.0 with a unified model registry -- no direct Anthropic API calls needed.

Here's the typical flow for an AI request:

1. You select a model from the unified registry
2. The request goes through `getModelInstance()` in `lib/ai/ai-utils.ts`
3. The provider is determined via `getProviderFromModelId()`
4. The model is instantiated with `customModel()`
5. The response is streamed back to you
6. Results are stored in PostgreSQL

<Card title="Structure" icon="folder" href="/setup/structure">
  Understand the full project structure of the codebase.
</Card>