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

# Use Flatkey with Claude Code for Discounted AI Coding

> Route Claude Code CLI traffic through Flatkey to access Claude models at up to 50% off official Anthropic pricing with two environment variable changes.

Anthropic's Claude Code is an agentic AI coding assistant that runs in your terminal. By setting the `ANTHROPIC_BASE_URL` environment variable, you can route all Claude Code requests through Flatkey and pay Flatkey's discounted rates on Claude model usage.

## Prerequisites

* Claude Code installed: `npm install -g @anthropic-ai/claude-code`
* A Flatkey account with an API key — [get one here](https://console.flatkey.ai/sign-up)

## Configuration

Set these two environment variables:

```bash theme={null}
export ANTHROPIC_BASE_URL="https://router.flatkey.ai"
export ANTHROPIC_API_KEY="sk-fk-your-flatkey-key"
```

To make the setting permanent, add them to your shell profile:

```bash ~/.zshrc theme={null}
export ANTHROPIC_BASE_URL="https://router.flatkey.ai"
export ANTHROPIC_API_KEY="sk-fk-your-flatkey-key"
```

<Warning>
  Set `ANTHROPIC_BASE_URL` to `https://router.flatkey.ai` — without a trailing `/v1`. The Claude Code CLI appends the correct path automatically.
</Warning>

## Configure with CC Switch

[CC Switch](https://ccswitch.io) is a third-party desktop configuration manager for coding assistants. You can also download it from the [official GitHub repository](https://github.com/farion1231/cc-switch).

1. Open CC Switch and select **Claude Code**.
2. Add a **Custom Provider** named `Flatkey`.
3. Set the base URL to `https://router.flatkey.ai` without a trailing `/v1`.
4. Enter your Flatkey API key (`sk-fk-...`) and activate the provider.
5. Fully quit and reopen Claude Code so it reloads the provider settings.
6. Send a small request, then confirm it in **Usage Logs** in the [Flatkey Console](https://console.flatkey.ai/usage-logs/common).

<Note>
  If your CC Switch version does not include a Flatkey preset, use **Custom Provider**. CC Switch is not a Flatkey product.
</Note>

## Running Claude Code

Use Claude Code exactly as you normally would:

```bash theme={null}
claude "Fix the bug in this file"
```

or interactively:

```bash theme={null}
claude
```

All requests are routed to Flatkey and billed from your prepaid balance at discounted rates.

## Verifying the setup

Run a simple request and then check **Usage Logs** in your [Flatkey Console](https://console.flatkey.ai/usage-logs/common). You should see the Claude request logged with its model ID, token counts, and cost.

## Savings estimate

Using Claude Sonnet (a popular choice for Claude Code) through Flatkey:

|                                   | Official price  | Flatkey (after \$200 bonus) |
| --------------------------------- | --------------- | --------------------------- |
| `claude-sonnet-4-5` input         | \$3 / 1M tokens | \~\$1.6 / 1M tokens         |
| `claude-haiku-4-5-20251001` input | \$1 / 1M tokens | \~\$0.53 / 1M tokens        |

On a typical Claude Code session of 50K input tokens, using Sonnet, that is:

* Official: \~\$0.15 per session
* Flatkey: \~\$0.08 per session

<Tip>
  Heavy Claude Code users benefit most from the \$200 top-up tier — the bonus credit effectively gives you an extra month of usage on top of the model discount.
</Tip>

## Troubleshooting

| Issue                     | Fix                                                               |
| ------------------------- | ----------------------------------------------------------------- |
| `Authentication failed`   | Confirm `ANTHROPIC_API_KEY` is your Flatkey key (`sk-fk-...`)     |
| `Could not connect`       | Verify `ANTHROPIC_BASE_URL` is set to `https://router.flatkey.ai` |
| `Insufficient balance`    | Add credit at [console.flatkey.ai](https://console.flatkey.ai)    |
| Requests not in dashboard | Check environment variables are exported in the current shell     |