diff --git a/packages/app/src/components/worktree-setup-callout-policy.test.ts b/packages/app/src/components/worktree-setup-callout-policy.test.ts
index d78e76179..45d0d807c 100644
--- a/packages/app/src/components/worktree-setup-callout-policy.test.ts
+++ b/packages/app/src/components/worktree-setup-callout-policy.test.ts
@@ -13,28 +13,13 @@ function gitWorkspace(
     projectId: "project-1",
     projectKind: "git",
     projectRootPath: "/repo/project-1",
-    project: { checkout: { mainRepoRoot: "/repo/main-project-1" } },
     ...overrides,
   };
 }
 
 describe("selectActiveGitWorkspaceProject", () => {
-  it("selects the active git workspace project from checkout metadata", () => {
+  it("selects the exact active git workspace project root", () => {
     expect(selectActiveGitWorkspaceProject("server-1", gitWorkspace())).toEqual({
-      serverId: "server-1",
-      projectId: "project-1",
-      projectKey: "project-1",
-      repoRoot: "/repo/main-project-1",
-    });
-  });
-
-  it("falls back to the workspace project root when checkout metadata has no main root", () => {
-    expect(
-      selectActiveGitWorkspaceProject(
-        "server-1",
-        gitWorkspace({ project: { checkout: { mainRepoRoot: null } } }),
-      ),
-    ).toEqual({
       serverId: "server-1",
       projectId: "project-1",
       projectKey: "project-1",
@@ -65,10 +50,7 @@ describe("selectActiveGitWorkspaceProject", () => {
       null,
     );
     expect(
-      selectActiveGitWorkspaceProject(
-        "server-1",
-        gitWorkspace({ projectRootPath: " ", project: null }),
-      ),
+      selectActiveGitWorkspaceProject("server-1", gitWorkspace({ projectRootPath: " " })),
     ).toBe(null);
   });
 });
diff --git a/packages/app/src/components/worktree-setup-callout-policy.ts b/packages/app/src/components/worktree-setup-callout-policy.ts
index 718f9ae51..925d75414 100644
--- a/packages/app/src/components/worktree-setup-callout-policy.ts
+++ b/packages/app/src/components/worktree-setup-callout-policy.ts
@@ -9,11 +9,6 @@ export interface WorktreeSetupWorkspaceInput {
   projectGroupKey?: string | null;
   projectKind: string;
   projectRootPath: string;
-  project?: {
-    checkout?: {
-      mainRepoRoot?: string | null;
-    } | null;
-  } | null;
 }
 
 export interface ActiveGitWorkspaceProject {
@@ -53,7 +48,7 @@ export function selectActiveGitWorkspaceProject(
     projectId,
     projectGroupKey: workspace.projectGroupKey,
   });
-  const repoRoot = (workspace.project?.checkout?.mainRepoRoot ?? workspace.projectRootPath).trim();
+  const repoRoot = workspace.projectRootPath.trim();
   if (!projectId || !repoRoot) {
     return null;
   }
diff --git a/packages/app/src/projects/project-group-key.ts b/packages/app/src/projects/project-group-key.ts
index 0d06a2e14..fd0aec778 100644
--- a/packages/app/src/projects/project-group-key.ts
+++ b/packages/app/src/projects/project-group-key.ts
@@ -7,7 +7,9 @@ export function resolveProjectGroupKey(input: {
   // COMPAT(projectGroupKey): added in v0.2.4 on 2026-07-28; remove after 2027-01-28.
   // Older daemons used remote/path-shaped project IDs as their grouping key. New opaque IDs
   // must remain host-local when the new field is absent.
-  return input.projectId.startsWith("prj_")
-    ? `host:${input.serverId}:project:${input.projectId}`
-    : input.projectId;
+  return input.projectId.startsWith("prj_") ? frameHostProjectKey(input) : input.projectId;
+}
+
+export function frameHostProjectKey(input: { serverId: string; projectId: string }): string {
+  return `host:${encodeURIComponent(input.serverId)}:project:${encodeURIComponent(input.projectId)}`;
 }
diff --git a/packages/app/src/projects/project-settings-target.ts b/packages/app/src/projects/project-settings-target.ts
index d0c09805e..c580a472a 100644
--- a/packages/app/src/projects/project-settings-target.ts
+++ b/packages/app/src/projects/project-settings-target.ts
@@ -1,3 +1,5 @@
+import { frameHostProjectKey } from "./project-group-key";
+
 interface ProjectSettingsTarget {
   projectKey: string;
   hosts: ReadonlyArray<{ serverId: string; projectId?: string; isOnline?: boolean }>;
@@ -9,7 +11,7 @@ export function resolveHostProjectSettingsRouteKey(host: {
 }): string | null {
   const projectId = host.projectId?.trim();
   if (!projectId) return null;
-  return `host:${encodeURIComponent(host.serverId)}:project:${encodeURIComponent(projectId)}`;
+  return frameHostProjectKey({ serverId: host.serverId, projectId });
 }
 
 export function resolveProjectSettingsRouteKey(project: ProjectSettingsTarget): string {
diff --git a/packages/app/src/projects/workspace-structure.test.ts b/packages/app/src/projects/workspace-structure.test.ts
index 3f32c2201..80a41192f 100644
--- a/packages/app/src/projects/workspace-structure.test.ts
+++ b/packages/app/src/projects/workspace-structure.test.ts
@@ -6,10 +6,11 @@ function workspace(input: {
   id: string;
   projectName: string;
   projectCustomName: string | null;
+  projectId?: string;
 }): WorkspaceDescriptor {
   return {
     id: input.id,
-    projectId: `project-${input.id}`,
+    projectId: input.projectId ?? `project-${input.id}`,
     projectGroupKey: "remote:github.com/acme/app",
     projectDisplayName: input.projectName,
     projectCustomName: input.projectCustomName,
@@ -50,4 +51,42 @@ describe("buildWorkspaceStructureProjects", () => {
       }),
     ]);
   });
+
+  it("frames ambiguous host placements without alias collisions", () => {
+    const projects = buildWorkspaceStructureProjects({
+      sessions: [
+        {
+          serverId: "a",
+          workspaces: [
+            workspace({
+              id: "a-1",
+              projectId: "remote:x/foo:project:/c",
+              projectName: "first",
+              projectCustomName: null,
+            }),
+            workspace({
+              id: "a-2",
+              projectId: "other",
+              projectName: "other",
+              projectCustomName: null,
+            }),
+          ],
+        },
+        {
+          serverId: "a:project:remote:x/foo",
+          workspaces: [
+            workspace({
+              id: "b",
+              projectId: "/c",
+              projectName: "second",
+              projectCustomName: null,
+            }),
+          ],
+        },
+      ],
+    });
+
+    expect(projects).toHaveLength(3);
+    expect(new Set(projects.map((project) => project.projectKey)).size).toBe(3);
+  });
 });
diff --git a/packages/app/src/projects/workspace-structure.ts b/packages/app/src/projects/workspace-structure.ts
index 8d6feba43..0023c6c5a 100644
--- a/packages/app/src/projects/workspace-structure.ts
+++ b/packages/app/src/projects/workspace-structure.ts
@@ -1,6 +1,6 @@
 import type { EmptyProjectDescriptor, WorkspaceDescriptor } from "@/stores/session-store";
 import { projectDisplayNameFromProjectId } from "@/utils/project-display-name";
-import { resolveProjectGroupKey } from "@/projects/project-group-key";
+import { frameHostProjectKey, resolveProjectGroupKey } from "@/projects/project-group-key";
 
 export interface WorkspaceStructureHostPlacement {
   serverId: string;
@@ -104,9 +104,7 @@ function resolveUnambiguousProjectGroupKey(input: {
   ambiguousGroupKeys: ReadonlySet<string>;
 }): string {
   const groupKey = resolveProjectGroupKey(input);
-  return input.ambiguousGroupKeys.has(groupKey)
-    ? `host:${input.serverId}:project:${input.projectId}`
-    : groupKey;
+  return input.ambiguousGroupKeys.has(groupKey) ? frameHostProjectKey(input) : groupKey;
 }
 
 export function buildWorkspaceStructureProjects(input: {
diff --git a/packages/server/src/server/project-group-key.test.ts b/packages/server/src/server/project-group-key.test.ts
index 56c80dc5d..8a9b6faee 100644
--- a/packages/server/src/server/project-group-key.test.ts
+++ b/packages/server/src/server/project-group-key.test.ts
@@ -159,6 +159,21 @@ describe("deriveProjectGroupKey", () => {
     );
   });
 
+  test("preserves leading whitespace in SCP repository paths", () => {
+    const rootPath = path.resolve("repo");
+    const derive = (remoteUrl: string) =>
+      deriveProjectGroupKey({
+        rootPath,
+        remoteUrl,
+        worktreeRoot: rootPath,
+        mainRepoRoot: null,
+      });
+
+    expect(derive("git@example.com: acme/repo.git")).not.toBe(
+      derive("git@example.com:acme/repo.git"),
+    );
+  });
+
   test("does not parse drive-relative Windows paths as SCP remotes", () => {
     const rootPath = path.resolve("repo");
 
diff --git a/packages/server/src/server/project-group-key.ts b/packages/server/src/server/project-group-key.ts
index c78357d26..0698919ce 100644
--- a/packages/server/src/server/project-group-key.ts
+++ b/packages/server/src/server/project-group-key.ts
@@ -50,9 +50,8 @@ function encodeSelectedPath(selectedPath: string): string {
 }
 
 function deriveRemoteProjectGroupKey(remoteUrl: string | null): string | null {
-  const trimmed = remoteUrl?.trim();
-  if (!trimmed) return null;
-  const remote = parseRemoteLocation(trimmed);
+  if (!remoteUrl?.trim()) return null;
+  const remote = parseRemoteLocation(remoteUrl);
   if (!remote) return null;
   const cleanedPath = normalizeRemotePath(
     remote.path,
@@ -143,7 +142,7 @@ function normalizeRemotePath(
   decodePercentEncoding: boolean,
   stripDotGitSuffix: boolean,
 ): string {
-  const trimmedPath = remotePath.trim().replace(/\/+$/, "");
+  const trimmedPath = remotePath.replace(/\/+$/, "");
   const pathForEncoding = preserveLeadingSlash ? trimmedPath : trimmedPath.replace(/^\/+/, "");
   const segments = pathForEncoding.split("/");
   const decodedSegments = segments.map((segment) => {