diff --git a/packages/opencode/src/server/shared/workspace-routing.ts b/packages/opencode/src/server/shared/workspace-routing.ts
index 366c455dd6bb..c57e392c2191 100644
--- a/packages/opencode/src/server/shared/workspace-routing.ts
+++ b/packages/opencode/src/server/shared/workspace-routing.ts
@@ -32,5 +32,14 @@ export function workspaceProxyURL(target: string | URL, requestURL: URL) {
   proxyURL.search = requestURL.search
   proxyURL.hash = requestURL.hash
   proxyURL.searchParams.delete("workspace")
+  // The SDK rewrites the client's `x-opencode-directory` header into a
+  // `?directory=` query before sending. When the request is then proxied
+  // to a remote workspace, that local-machine path leaks through and the
+  // remote falls back to `worktree="/"` because the path doesn't exist on
+  // its filesystem — which corrupts downstream `path.relative()` callers
+  // (notably `sessionListQuery`) and wipes the TUI's session list.
+  // Strip it so the workspace adapter's `target.headers["x-opencode-directory"]`
+  // (the workspace's directory on the remote) wins.
+  proxyURL.searchParams.delete("directory")
   return proxyURL
 }
diff --git a/packages/opencode/test/server/workspace-routing.test.ts b/packages/opencode/test/server/workspace-routing.test.ts
index a921ae2774c5..f851fc00087e 100644
--- a/packages/opencode/test/server/workspace-routing.test.ts
+++ b/packages/opencode/test/server/workspace-routing.test.ts
@@ -75,6 +75,18 @@ describe("workspaceProxyURL", () => {
     expect(result.searchParams.get("keep")).toBe("yes")
   })
 
+  test("strips directory query so the remote uses its own working directory", () => {
+    // The SDK rewrites the client's `x-opencode-directory` header into a
+    // `?directory=` query before sending. Forwarding that local-machine
+    // path to a remote workspace makes the remote fall back to
+    // `worktree="/"` (the path doesn't exist on its filesystem) and
+    // corrupts downstream `path.relative()` callers.
+    const url = new URL("http://localhost/path?workspace=ws_123&directory=%2FUsers%2Falice%2Fproj")
+    const result = workspaceProxyURL("http://remote:8080", url)
+    expect(result.searchParams.get("workspace")).toBeNull()
+    expect(result.searchParams.get("directory")).toBeNull()
+  })
+
   test("preserves hash from request", () => {
     const url = new URL("http://localhost/page#section")
     const result = workspaceProxyURL("http://remote:8080", url)