> This page is for version v2025-04-21.
> For other versions, use one of these documentation indexes:
> - v2026-02-09 (default): https://docs.extend.ai/2026-02-09/llms.txt
> - v2025-04-21: https://docs.extend.ai/2025-04-21/llms.txt
> - v2024-12-23: https://docs.extend.ai/2024-12-23/llms.txt

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.extend.ai/llms.txt
> Use this file to discover all available pages before exploring further.
>
> ## API version
> The current API version is `2026-02-09`, served at the site root (no version prefix in URLs).
> If this page URL contains `/2025-04-21/` or `/2024-12-23/`, you are reading an older API version.
> Prefer the current docs at https://docs.extend.ai/llms.txt unless the user explicitly needs that older version.
> Do not treat older-version pages as the source of truth for new integrations.

> Extend's deployment environments and regional options for meeting data residency and regulatory requirements, including the base URL for each environment.

Extend operates multiple deployments to support different regulatory and data residency requirements.

> **Note**
>
> If you're unsure which environment you are in or should be in, reach out to us!

## Available Environments

* **Production (Default)**: `https://api.extend.ai` - Our primary production environment
* **US2**: `https://api.us2.extend.app` - Additional US production deployment
* **EU1**: `https://api.eu1.extend.ai` - European deployment for EU data residency requirements

| Deployment           | Base URL                     | CLI `EXTEND_REGION` |
| -------------------- | ---------------------------- | ------------------- |
| Production (Default) | `https://api.extend.ai`      | `us`                |
| US2                  | `https://api.us2.extend.app` | `us2`               |
| EU1                  | `https://api.eu1.extend.ai`  | `eu`                |

> **Note**
>
> The US2 deployment is served from the `extend.app` domain (not `extend.ai`). This is intentional — use the host exactly as shown above.

## Configuring Your SDK

By default, our SDKs connect to the production endpoint (`api.extend.ai`). To use a different deployment, configure your SDK with the appropriate base URL:

```python
from extend_ai import Extend

# US2
client_us2 = Extend(
  token="YOUR_API_KEY_HERE",
  base_url="https://api.us2.extend.app"
)

# EU1
client_eu1 = Extend(
  token="YOUR_API_KEY_HERE",
  base_url="https://api.eu1.extend.ai"
)
```

```typescript
import { ExtendClient } from "extend-ai";

// US2
const clientUs2 = new ExtendClient({
  token: "YOUR_API_KEY_HERE",
  baseUrl: "https://api.us2.extend.app"
});

// EU1
const clientEu1 = new ExtendClient({
  token: "YOUR_API_KEY_HERE",
  baseUrl: "https://api.eu1.extend.ai"
});
```

```java
import ai.extend.ExtendClient;

// US2
ExtendClient clientUs2 = ExtendClient.builder()
        .apiKey("YOUR_API_KEY_HERE")
        .url("https://api.us2.extend.app")
        .build();

// EU1
ExtendClient clientEu1 = ExtendClient.builder()
        .apiKey("YOUR_API_KEY_HERE")
        .url("https://api.eu1.extend.ai")
        .build();
```

```go
import (
	client "github.com/extend-hq/extend-go-sdk/client"
	option "github.com/extend-hq/extend-go-sdk/option"
)

// US2
clientUs2 := client.NewClient(
	option.WithToken("YOUR_API_KEY_HERE"),
	option.WithBaseURL("https://api.us2.extend.app"),
)

// EU1
clientEu1 := client.NewClient(
	option.WithToken("YOUR_API_KEY_HERE"),
	option.WithBaseURL("https://api.eu1.extend.ai"),
)
```