diff --git a/sdk/src/flowmesh/ssh.py b/sdk/src/flowmesh/ssh.py
index d67f30f..95f6258 100644
--- a/sdk/src/flowmesh/ssh.py
+++ b/sdk/src/flowmesh/ssh.py
@@ -8,6 +8,7 @@
 
 import yaml
 
+from ._constants import API_VERSION_PREFIX
 from .exceptions import FlowMeshError
 from .models.common import TaskStatus
 from .models.tasks import TaskInfo
@@ -159,9 +160,8 @@ def ssh_proxy_url(base_url: str, task_id: str) -> str:
     """Build the websocket proxy URL for an SSH task."""
     base = urlsplit(base_url)
     ws_scheme = "wss" if base.scheme == "https" else "ws"
-    return urlunsplit(
-        (ws_scheme, base.netloc, f"/api/v1/ssh/tasks/{task_id}/proxy", "", "")
-    )
+    path = f"{base.path.rstrip('/')}{API_VERSION_PREFIX}/ssh/tasks/{task_id}/proxy"
+    return urlunsplit((ws_scheme, base.netloc, path, "", ""))
 
 
 def ssh_connection_commands(
diff --git a/tests/sdk/test_resource_helpers.py b/tests/sdk/test_resource_helpers.py
index 131f388..c3c2f22 100644
--- a/tests/sdk/test_resource_helpers.py
+++ b/tests/sdk/test_resource_helpers.py
@@ -317,6 +317,38 @@ def test_proxy_url_and_connection_commands(self) -> None:
         cmds = ssh_connection_commands("task-1", ssh_info, base_url=base_url)
         assert isinstance(cmds, list)
 
+    def test_proxy_url_root_mounted(self) -> None:
+        assert (
+            ssh_proxy_url("https://example.com", "task-1")
+            == "wss://example.com/api/v1/ssh/tasks/task-1/proxy"
+        )
+
+    def test_proxy_url_preserves_base_path(self) -> None:
+        assert (
+            ssh_proxy_url("https://example.com:8000/flowmesh", "task-1")
+            == "wss://example.com:8000/flowmesh/api/v1/ssh/tasks/task-1/proxy"
+        )
+
+    def test_proxy_url_scheme_conversion(self) -> None:
+        assert ssh_proxy_url("http://localhost:8000", "t").startswith("ws://")
+        assert ssh_proxy_url("https://localhost:8000", "t").startswith("wss://")
+
+    def test_proxy_url_trailing_slash(self) -> None:
+        assert (
+            ssh_proxy_url("https://example.com:8000/flowmesh/", "task-1")
+            == "wss://example.com:8000/flowmesh/api/v1/ssh/tasks/task-1/proxy"
+        )
+
+    def test_connection_commands_proxy_mode_embeds_base_path(self) -> None:
+        ssh_info = {"mode": "proxy", "username": "flowmesh", "host": "h", "port": 22}
+        cmds = ssh_connection_commands(
+            "task-1", ssh_info, base_url="https://example.com:8000/flowmesh"
+        )
+        proxy_cmd = next(cmd for label, cmd in cmds if label == "ssh (proxy)")
+        assert (
+            "wss://example.com:8000/flowmesh/api/v1/ssh/tasks/task-1/proxy" in proxy_cmd
+        )
+
     def test_detect_public_key_prefers_standard_keys(self, tmp_path: Path) -> None:
         ssh_dir = tmp_path / ".ssh"
         ssh_dir.mkdir()