fix(devbox): get_tunnel_url now derives tunnel domain from base url

src/runloop_api_client/sdk/async_devbox.py

@@ -161,7 +161,9 @@ async def get_tunnel_url(
         tunnel_view = await self.get_tunnel(**options)
         if tunnel_view is None:
             return None
-        return f"https://{port}-{tunnel_view.tunnel_key}.tunnel.runloop.ai"
+        api_host = self._client.base_url.host
+        base_domain = api_host[4:] if api_host.startswith("api.") else api_host
+        return f"https://{port}-{tunnel_view.tunnel_key}.tunnel.{base_domain}"
 
     async def logs(
         self,

src/runloop_api_client/sdk/devbox.py

@@ -160,7 +160,9 @@ def get_tunnel_url(
         tunnel_view = self.get_tunnel(**options)
         if tunnel_view is None:
             return None
-        return f"https://{port}-{tunnel_view.tunnel_key}.tunnel.runloop.ai"
+        api_host = self._client.base_url.host
+        base_domain = api_host[4:] if api_host.startswith("api.") else api_host
+        return f"https://{port}-{tunnel_view.tunnel_key}.tunnel.{base_domain}"
 
     def logs(
         self,

tests/sdk/async_devbox/test_core.py

@@ -9,6 +9,7 @@
 from types import SimpleNamespace
 from unittest.mock import AsyncMock
 
+import httpx
 import pytest
 
 from tests.sdk.conftest import MockDevboxView
@@ -377,13 +378,36 @@ async def test_get_tunnel_url_constructs_url(self, mock_async_client: AsyncMock)
             tunnel=tunnel_view,
         )
         mock_async_client.devboxes.retrieve = AsyncMock(return_value=devbox_view_with_tunnel)
+        mock_async_client.base_url = httpx.URL("https://api.runloop.ai")
 
         devbox = AsyncDevbox(mock_async_client, "dbx_123")
         result = await devbox.get_tunnel_url(8080)
 
         assert result == "https://8080-abc123xyz.tunnel.runloop.ai"
         mock_async_client.devboxes.retrieve.assert_called_once_with("dbx_123")
 
+    @pytest.mark.asyncio
+    async def test_get_tunnel_url_derives_domain_from_base_url(self, mock_async_client: AsyncMock) -> None:
+        """Test get_tunnel_url derives tunnel domain from client base_url."""
+        tunnel_view = SimpleNamespace(
+            tunnel_key="abc123xyz",
+            auth_mode="open",
+            create_time_ms=1234567890000,
+        )
+        devbox_view_with_tunnel = SimpleNamespace(
+            id="dbx_123",
+            status="running",
+            tunnel=tunnel_view,
+        )
+        mock_async_client.devboxes.retrieve = AsyncMock(return_value=devbox_view_with_tunnel)
+        devbox = AsyncDevbox(mock_async_client, "dbx_123")
+
+        mock_async_client.base_url = httpx.URL("https://api.runloop.pro")
+        assert await devbox.get_tunnel_url(8080) == "https://8080-abc123xyz.tunnel.runloop.pro"
+
+        mock_async_client.base_url = httpx.URL("http://127.0.0.1:8080")
+        assert await devbox.get_tunnel_url(8080) == "https://8080-abc123xyz.tunnel.127.0.0.1"
+
     @pytest.mark.asyncio
     async def test_get_tunnel_url_returns_none_when_no_tunnel(self, mock_async_client: AsyncMock) -> None:
         """Test get_tunnel_url returns None when no tunnel is enabled."""

tests/sdk/devbox/test_core.py

@@ -9,6 +9,7 @@
 from types import SimpleNamespace
 from unittest.mock import Mock
 
+import httpx
 import pytest
 
 from tests.sdk.conftest import (
@@ -373,13 +374,35 @@ def test_get_tunnel_url_constructs_url(self, mock_client: Mock) -> None:
             tunnel=tunnel_view,
         )
         mock_client.devboxes.retrieve.return_value = devbox_view_with_tunnel
+        mock_client.base_url = httpx.URL("https://api.runloop.ai")
 
         devbox = Devbox(mock_client, "dbx_123")
         result = devbox.get_tunnel_url(8080)
 
         assert result == "https://8080-abc123xyz.tunnel.runloop.ai"
         mock_client.devboxes.retrieve.assert_called_once_with("dbx_123")
 
+    def test_get_tunnel_url_derives_domain_from_base_url(self, mock_client: Mock) -> None:
+        """Test get_tunnel_url derives tunnel domain from client base_url."""
+        tunnel_view = SimpleNamespace(
+            tunnel_key="abc123xyz",
+            auth_mode="open",
+            create_time_ms=1234567890000,
+        )
+        devbox_view_with_tunnel = SimpleNamespace(
+            id="dbx_123",
+            status="running",
+            tunnel=tunnel_view,
+        )
+        mock_client.devboxes.retrieve.return_value = devbox_view_with_tunnel
+        devbox = Devbox(mock_client, "dbx_123")
+
+        mock_client.base_url = httpx.URL("https://api.runloop.pro")
+        assert devbox.get_tunnel_url(8080) == "https://8080-abc123xyz.tunnel.runloop.pro"
+
+        mock_client.base_url = httpx.URL("http://127.0.0.1:8080")
+        assert devbox.get_tunnel_url(8080) == "https://8080-abc123xyz.tunnel.127.0.0.1"
+
     def test_get_tunnel_url_returns_none_when_no_tunnel(self, mock_client: Mock) -> None:
         """Test get_tunnel_url returns None when no tunnel is enabled."""
         devbox_view_no_tunnel = SimpleNamespace(