diff --git a/packages/opencode/navigator.ts b/packages/opencode/navigator.ts
index 9e04a42..bc91f08 100644
--- a/packages/opencode/navigator.ts
+++ b/packages/opencode/navigator.ts
@@ -87,7 +87,7 @@ type NavigatorContext = {
   legacyClient: (directory: string) => NavigatorLegacyClient;
 };
 
-type NativeWorktree = { directory: string; name: string; branch?: string; id?: string; type: "worktree" | "rift" };
+type NativeWorktree = { directory: string; name: string; branch?: string; id?: string; projectID?: string; type: "worktree" | "rift" };
 
 const explicitNavigatorUse = "Use only when the user explicitly asks to create or manage native OpenCode sessions, worktrees, or a multi-session workflow. Do not use for subagent delegation; use the built-in task tool instead.";
 
@@ -153,6 +153,7 @@ function normalizeRiftWorkspace(workspace: NativeWorkspace): NativeWorktree | un
     type: "rift",
     directory: workspace.directory,
     name: workspace.name || path.basename(workspace.directory),
+    ...(workspace.projectID ? { projectID: workspace.projectID } : {}),
     ...(workspace.branch ? { branch: workspace.branch } : {}),
   };
 }
@@ -179,7 +180,36 @@ async function listManagedWorktrees(client: NavigatorClient, checkout: string, p
   const worktrees = values.map(normalizeWorktree).filter((item) => !sameDirectory(item.directory, checkout));
   if (!projectID) return worktrees;
   const rifts = await listRiftWorkspaces(client, checkout, projectID).catch(() => []);
-  return [...worktrees, ...rifts];
+  const unique = new Map(worktrees.map((item) => [normalizeDirectory(item.directory), item]));
+  for (const rift of rifts) unique.set(normalizeDirectory(rift.directory), rift);
+  return [...unique.values()];
+}
+
+async function removeCreatedWorkspace(client: NavigatorClient, checkout: string, workspace: NativeWorktree) {
+  if (workspace.type === "rift") {
+    const api = workspaceApi(client);
+    if (!api?.workspace?.remove || !workspace.id) throw new Error("OpenCode Rift workspace removal is unavailable");
+    const response = await api.workspace.remove({ id: workspace.id, directory: checkout });
+    if (response.error !== undefined) failResponse(response.error, `OpenCode Rift workspace rollback for ${workspace.directory}`);
+    return;
+  }
+  responseData(await client.worktree.remove({
+    directory: checkout,
+    worktreeRemoveInput: { directory: workspace.directory },
+  }), `OpenCode worktree rollback for ${workspace.directory}`);
+}
+
+async function rollbackCreatedWorkspaces(client: NavigatorClient, checkout: string, workspaces: NativeWorktree[]) {
+  const unique = new Map(workspaces.map((item) => [normalizeDirectory(item.directory), item]));
+  const failures: string[] = [];
+  for (const workspace of unique.values()) {
+    try {
+      await removeCreatedWorkspace(client, checkout, workspace);
+    } catch (error) {
+      failures.push(`${workspace.directory}: ${error instanceof Error ? error.message : String(error)}`);
+    }
+  }
+  return failures;
 }
 
 async function activeSessionIDs(client: NavigatorClient, navigator: NavigatorContext) {
@@ -559,6 +589,11 @@ export function createNavigatorTools(
               const normalized = normalizeRiftWorkspace(workspace);
               if (!normalized) throw new Error("OpenCode Rift workspace create returned no directory");
               createdWorktree = normalized;
+              if (normalized.projectID && normalized.projectID !== navigator.projectID) {
+                throw new Error(
+                  `OpenCode registered workspace ${normalized.id} to project ${normalized.projectID}; expected ${navigator.projectID}`,
+                );
+              }
             } else {
               const worktree = responseData(
                 await client.worktree.create({
@@ -577,9 +612,15 @@ export function createNavigatorTools(
             const worktreesAfter = await listManagedWorktrees(client, navigator.checkout, navigator.projectID).catch(() => []);
             const before = new Set(worktreesBefore.map((item) => normalizeDirectory(item.directory)));
             const partial = worktreesAfter.filter((item) => !before.has(normalizeDirectory(item.directory)));
+            const created = createdWorktree ? [createdWorktree, ...partial] : partial;
+            const rollbackFailures = await rollbackCreatedWorkspaces(client, navigator.checkout, created);
             throw new Error(
               `Navigator could not create the requested workspace: ${error instanceof Error ? error.message : String(error)}` +
-              (partial.length ? `. Workspaces created and not removed: ${partial.map((item) => item.directory).join(", ")}` : ""),
+              (created.length
+                ? rollbackFailures.length
+                  ? `. Rollback failed for ${rollbackFailures.join("; ")}`
+                  : ". The partially created workspace was removed"
+                : ""),
             );
           }
         }
@@ -608,13 +649,30 @@ export function createNavigatorTools(
                 "OpenCode session create",
               );
         } catch (error) {
+          const rollbackFailures = createdWorktree
+            ? await rollbackCreatedWorkspaces(client, navigator.checkout, [createdWorktree])
+            : [];
           throw new Error(
             `Navigator session creation failed: ${error instanceof Error ? error.message : String(error)}` +
-            (createdWorktree ? `. Worktree created: ${createdWorktree.name} (${createdWorktree.directory}) and was not removed` : ""),
+            (createdWorktree
+              ? rollbackFailures.length
+                ? `. Workspace created at ${createdWorktree.directory}, but rollback failed: ${rollbackFailures.join("; ")}`
+                : `. Workspace ${createdWorktree.directory} was rolled back`
+              : ""),
           );
         }
         if (session.projectID !== navigator.projectID) {
-          throw new Error(`Created session ${session.id} belongs to an unexpected project; it was not prompted`);
+          const rollbackFailures = createdWorktree
+            ? await rollbackCreatedWorkspaces(client, navigator.checkout, [createdWorktree])
+            : [];
+          throw new Error(
+            `Created session ${session.id} belongs to project ${session.projectID}; expected ${navigator.projectID}. It was not prompted` +
+            (createdWorktree
+              ? rollbackFailures.length
+                ? `. Workspace rollback failed: ${rollbackFailures.join("; ")}`
+                : `. Workspace ${createdWorktree.directory} was rolled back`
+              : ""),
+          );
         }
 
         try {
@@ -654,7 +712,7 @@ export function createNavigatorTools(
           sessionID: session.id,
           directory,
           ...(createdWorktree
-            ? { worktree: { created: true, type: createdWorktree.type, name: createdWorktree.name, ...(createdWorktree.branch ? { branch: createdWorktree.branch } : {}) } }
+              ? { worktree: { created: true, type: createdWorktree.type, name: createdWorktree.name, ...(createdWorktree.id ? { id: createdWorktree.id } : {}), ...(createdWorktree.branch ? { branch: createdWorktree.branch } : {}) } }
             : {}),
         });
       },
diff --git a/packages/opencode/rift-workspace.ts b/packages/opencode/rift-workspace.ts
index 8a33060..9ad0727 100644
--- a/packages/opencode/rift-workspace.ts
+++ b/packages/opencode/rift-workspace.ts
@@ -36,7 +36,7 @@ type RiftAdapterOptions = {
 
 type ExperimentalWorkspaceInput = {
   experimental_workspace?: { register(type: string, adapter: WorkspaceAdapter): void };
-  project?: { id?: string };
+  project?: { id?: string; path?: string };
   worktree?: string;
   directory?: string;
 };
@@ -103,7 +103,14 @@ export function createRiftWorkspaceAdapter(rift: RiftModule, options: RiftAdapte
         copyAll: true,
       }));
       if (created !== expected) {
-        throw new Error(`Rift created ${created}, but OpenCode registered ${expected}`);
+        try {
+          rift.remove({ at: created });
+        } catch (error) {
+          throw new Error(
+            `Rift created ${created}, but OpenCode registered ${expected}. Rollback failed: ${error instanceof Error ? error.message : String(error)}`,
+          );
+        }
+        throw new Error(`Rift created ${created}, but OpenCode registered ${expected}. The created Rift was removed`);
       }
     },
     list() {
@@ -129,7 +136,9 @@ export function createRiftWorkspaceAdapter(rift: RiftModule, options: RiftAdapte
 export async function registerRiftWorkspaceAdapter(input: ExperimentalWorkspaceInput, logger: Logger) {
   const registrar = input.experimental_workspace;
   const projectID = input.project?.id;
-  const sourceDirectory = input.worktree ?? input.directory;
+  // A plugin loaded inside a managed workspace still belongs to the stable project checkout.
+  // Using input.worktree here would recursively nest new Rifts below the current Rift.
+  const sourceDirectory = input.project?.path ?? input.directory ?? input.worktree;
   if (!registrar || !projectID || !sourceDirectory) return;
 
   let rift: RiftModule;
diff --git a/packages/opencode/test/navigator.test.ts b/packages/opencode/test/navigator.test.ts
index 10b2940..dedbbdd 100644
--- a/packages/opencode/test/navigator.test.ts
+++ b/packages/opencode/test/navigator.test.ts
@@ -113,6 +113,34 @@ describe("Kompass Navigator", () => {
     assert.deepEqual(output.worktrees, [{ directory: "/repo-worktree", name: "repo-worktree", type: "worktree" }]);
   });
 
+  test("deduplicates native and Rift workspace entries by directory", async () => {
+    const client = createClient({ worktree: { list: async () => response(["/repo-shared"]) } });
+    client.experimental = {
+      workspace: {
+        adapter: { list: async () => response([{ type: "rift" }]) },
+        syncList: async () => response(undefined),
+        list: async () => response([{
+          id: "wrk_rift",
+          type: "rift",
+          name: "shared",
+          directory: "/repo-shared",
+          projectID: "project-1",
+        }]),
+        create: async () => response(undefined),
+        remove: async () => response(undefined),
+      },
+    };
+
+    const output = JSON.parse(await (tools(client).worktree_list as any).execute({}, context()));
+    assert.deepEqual(output.worktrees, [{
+      id: "wrk_rift",
+      projectID: "project-1",
+      type: "rift",
+      directory: "/repo-shared",
+      name: "shared",
+    }]);
+  });
+
   test("rejects foreign sessions", async () => {
     const client = createClient({
       session: { get: async () => response({ data: session("foreign", "/repo", "project-2") }) },
@@ -356,7 +384,7 @@ describe("Kompass Navigator", () => {
 
     assert.deepEqual(workspaceCreates, [{ directory: "/repo", type: "rift", extra: { name: "Parser Fix" } }]);
     assert.equal(sessionCreates[0].location.directory, "/repo-rift");
-    assert.deepEqual(output.worktree, { created: true, type: "rift", name: "parser-fix" });
+    assert.deepEqual(output.worktree, { created: true, type: "rift", name: "parser-fix", id: "wrk_rift" });
   });
 
   test("reports resources created before a prompt failure", async () => {
@@ -371,14 +399,19 @@ describe("Kompass Navigator", () => {
   });
 
   test("reports a worktree created before a session failure", async () => {
-    const client = createClient({ session: { create: async () => { throw new Error("create failed"); } } });
+    const removes: any[] = [];
+    const client = createClient({
+      worktree: { remove: async (args: any) => { removes.push(args); return response(true); } },
+      session: { create: async () => { throw new Error("create failed"); } },
+    });
     await assert.rejects(
       (tools(client).session_create as any).execute({
         prompt: "implement it",
         environment: { type: "new_worktree" },
       }, context()),
-      /Worktree created: new \(\/repo-new\).*was not removed/,
+      /Workspace \/repo-new was rolled back/,
     );
+    assert.equal(removes[0].worktreeRemoveInput.directory, "/repo-new");
   });
 
   test("discovers a worktree left behind by a failed native create", async () => {
@@ -397,10 +430,44 @@ describe("Kompass Navigator", () => {
         prompt: "implement it",
         environment: { type: "new_worktree", startCommand: "false" },
       }, context()),
-      /Workspaces created and not removed: \/repo-partial/,
+      /partially created workspace was removed/,
     );
   });
 
+  test("rejects a foreign Rift workspace before creating a session and rolls it back", async () => {
+    const removes: any[] = [];
+    let sessionCreates = 0;
+    const client = createClient({
+      worktree: { list: async () => response([]) },
+      session: { create: async () => { sessionCreates += 1; return response({ data: session("created") }); } },
+    });
+    client.experimental = {
+      workspace: {
+        adapter: { list: async () => response([{ type: "rift" }]) },
+        syncList: async () => response(undefined),
+        list: async () => response([]),
+        create: async () => response({
+          id: "wrk_foreign",
+          type: "rift",
+          name: "foreign",
+          directory: "/repo-foreign",
+          projectID: "project-2",
+        }),
+        remove: async (args: any) => { removes.push(args); return response(undefined); },
+      },
+    };
+
+    await assert.rejects(
+      (tools(client).session_create as any).execute({
+        prompt: "implement it",
+        environment: { type: "new_worktree" },
+      }, context()),
+      /registered workspace wrk_foreign to project project-2; expected project-1.*partially created workspace was removed/,
+    );
+    assert.equal(sessionCreates, 0);
+    assert.deepEqual(removes, [{ id: "wrk_foreign", directory: "/repo" }]);
+  });
+
   test("rejects self send, wait, and interrupt", async () => {
     const navigator = tools();
     await assert.rejects(
diff --git a/packages/opencode/test/tool-registration.test.ts b/packages/opencode/test/tool-registration.test.ts
index 19751bb..e615b48 100644
--- a/packages/opencode/test/tool-registration.test.ts
+++ b/packages/opencode/test/tool-registration.test.ts
@@ -176,6 +176,29 @@ describe("createOpenCodeTools", () => {
     });
   });
 
+  test("Rift workspace adapter removes a snapshot created at an unexpected path", async () => {
+    const removed: string[] = [];
+    const sourceDirectory = path.join(os.tmpdir(), "kompass-rift-source");
+    const adapter = createRiftWorkspaceAdapter({
+      init: () => null,
+      create: () => path.join(os.tmpdir(), "unexpected-rift"),
+      remove: ({ at } = {}) => { if (at) removed.push(at); },
+      list: () => [],
+    }, { sourceDirectory, projectID: "project-1" });
+    const configured = await adapter.configure({
+      id: "wrk_1",
+      type: "rift",
+      name: "Parser Fix",
+      branch: null,
+      directory: null,
+      extra: null,
+      projectID: "project-1",
+    });
+
+    await assert.rejects(adapter.create(configured, {}), /created Rift was removed/);
+    assert.deepEqual(removed, [path.join(os.tmpdir(), "unexpected-rift")]);
+  });
+
   test("registers Navigator by default", async () => {
     await withTempHome(async () => {
       const navigatorClient = {