> For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt.

# Using the EU region

Use this guide if your organization was provisioned on [eu.tessl.io](https://eu.tessl.io). The web app is at `https://eu.tessl.io`, and the CLI uses the API at `https://api.eu.tessl.io`.

The CLI selects the EU region when you log in and remembers it. This requires Tessl CLI 0.114.0 or later. Check your version with `tessl --version`, and run `tessl cli update` if it's older.

## Log in

Log in with the `--region` flag:

```shell-session
tessl login --region eu
```

The CLI opens `https://eu.tessl.io` in your browser. Approve the login there. The CLI saves the EU region with your session, so later commands such as `tessl install` and `tessl workspace list` use the EU region without the flag.

If the browser can't reach your terminal, for example over SSH, use device login instead:

```shell-session
tessl login --region eu --device
```

The CLI shows a code and a link on `eu.tessl.io`. Open the link, sign in, and enter the code.

Plain `tessl login` also works. If you approve the login on `eu.tessl.io`, or your account belongs only to the EU region, the CLI signs you in to the EU region and saves it. If it has to switch region, it says so and asks you to approve the login a second time.

Confirm that the CLI is using the EU region by listing your workspaces:

```shell-session
tessl workspace list
```

The output lists the workspaces of your organization on `eu.tessl.io`.

## Pin a repository to the EU region

Add `"region": "eu"` to the repository's `tessl.json` to make `tessl` commands run inside that repository use the EU region. The `--region` flag and the `TESSL_REGION` environment variable still take precedence:

```json
{
  "name": "engteam/payments-service",
  "region": "eu",
  "dependencies": {}
}
```

Commit the change so everyone working in the repository, and any CI job, MCP server, or agent that runs `tessl` there, uses the EU region.

## How the CLI chooses a region

The CLI uses the first of these that is set:

1. The `--region` flag on the command, for example `tessl workspace list --region eu`.
2. The `TESSL_REGION` environment variable.
3. The `region` field in the nearest `tessl.json`.
4. The region you last logged in to.
5. The US region.

Valid regions are `us` and `eu`. `TESSL_REGION` also accepts the AWS region names `eu-west-1` and `us-east-1`.

If a login ends in a different region from the one `TESSL_REGION` or the repository's `tessl.json` selects, for example because you approved it on the other region's site, the CLI signs you out and names the setting to change. Later commands couldn't use that session.

If your environment sets `TESSL_API_BASE_URL`, `TESSL_WEB_BASE_URL`, or `TESSL_GLOBAL_DIR`, review or remove those overrides. They take precedence over the region and can select a different endpoint or storage directory.

## CI, MCP servers, and agents

In a repository pinned with `tessl.json`, you don't need any extra setting unless the environment sets `TESSL_REGION` to another region. Elsewhere, set `TESSL_REGION=eu` in the environment that starts the CLI. This applies to CI jobs, MCP servers, and agent integrations that run `tessl`, especially when they authenticate with an API key instead of a saved login.

For example, set the variable in a CI job environment:

```yaml
env:
  TESSL_REGION: eu
```

Recipe sandboxes launched from the EU instance select the EU region automatically. You do not need to set it in a skill, recipe, or schedule.

## Use both regions on one machine

The CLI keeps one saved login at a time. Logging in to the EU region replaces a US login, and the other way around. To work in the US region again, run `tessl login --region us`.

## Availability

The public registry and public publishing are not available in the EU region.