diff --git a/tests/close.test.ts b/tests/close.test.ts
new file mode 100644
index 0000000..27d56f3
--- /dev/null
+++ b/tests/close.test.ts
@@ -0,0 +1,183 @@
+import { expect, test, mock, spyOn, beforeEach, afterEach, describe } from "bun:test";
+import * as os from "node:os";
+import * as readline from "node:readline";
+import { closeMultiModel } from "../src/core/close";
+
+let originalBun$: typeof Bun.$ = (globalThis as any).Bun?.$;
+let mockCommandResponses: Record<string, { ok: boolean; stdout: string; stderr: string }> = {};
+let executedCommands: string[] = [];
+
+function setupMockBun$() {
+  const mockFn = mock((strings: TemplateStringsArray, ...values: any[]) => {
+    const parts = values[0] as string[];
+    const commandSignature = parts.join(" ");
+    executedCommands.push(commandSignature);
+    const response = mockCommandResponses[commandSignature] ?? { ok: true, stdout: "", stderr: "" };
+    return {
+      quiet: () => ({
+        nothrow: async () => ({
+          exitCode: response.ok ? 0 : 1,
+          stdout: { toString: () => response.stdout },
+          stderr: { toString: () => response.stderr },
+        }),
+      }),
+    };
+  });
+  (globalThis as any).Bun.$ = mockFn;
+  return mockFn;
+}
+
+function restoreOriginalBun$() {
+  (globalThis as any).Bun.$ = originalBun$;
+}
+
+describe("closeMultiModel", () => {
+  let bunMock: ReturnType<typeof setupMockBun$>;
+
+  beforeEach(() => {
+    spyOn(os, "homedir").mockReturnValue("/home/user");
+    bunMock = setupMockBun$();
+    executedCommands = [];
+    mockCommandResponses = {};
+  });
+
+  afterEach(() => {
+    restoreOriginalBun$();
+  });
+
+  test("kills existing session without cleanup", async () => {
+    mockCommandResponses["tmux has-session -t test-session"] = { ok: true, stdout: "", stderr: "" };
+    mockCommandResponses["tmux kill-session -t test-session"] = { ok: true, stdout: "", stderr: "" };
+    // No worktrees
+    mockCommandResponses["git worktree list --porcelain"] = { ok: true, stdout: "", stderr: "" };
+
+    const result = await closeMultiModel({ sessionName: "test-session", cleanupWorktrees: false, force: false });
+    expect(result.success).toBe(true);
+    expect(result.cleanupPerformed).toBe(false);
+    expect(result.worktreesRemoved).toEqual([]);
+    expect(executedCommands).toContain("tmux has-session -t test-session");
+    expect(executedCommands).toContain("tmux kill-session -t test-session");
+  });
+
+  test("no session exists, no cleanup", async () => {
+    mockCommandResponses["tmux has-session -t test-session"] = { ok: false, stdout: "", stderr: "" };
+    mockCommandResponses["git worktree list --porcelain"] = { ok: true, stdout: "", stderr: "" };
+
+    const result = await closeMultiModel({ sessionName: "test-session", cleanupWorktrees: false, force: false });
+    expect(result.success).toBe(true);
+    expect(result.cleanupPerformed).toBe(false);
+    expect(result.worktreesRemoved).toEqual([]);
+    expect(executedCommands).toContain("tmux has-session -t test-session");
+    // No kill-session should be issued
+    expect(executedCommands.some(c => c.startsWith("tmux kill-session"))).toBe(false);
+  });
+
+  test("cleanup works with worktrees and force, all succeeds", async () => {
+    mockCommandResponses["tmux has-session -t test-session"] = { ok: false, stdout: "", stderr: "" };
+    const worktreePath = "/home/user/.local/share/opencode/multi-model/test-session/model";
+    const worktreeListOutput = `worktree ${worktreePath}\nbranch refs/heads/opencode/test-session/model`;
+    mockCommandResponses["git worktree list --porcelain"] = { ok: true, stdout: worktreeListOutput, stderr: "" };
+    mockCommandResponses[`git worktree remove -f ${worktreePath}`] = { ok: true, stdout: "", stderr: "" };
+    mockCommandResponses["git branch -D opencode/test-session/model"] = { ok: true, stdout: "", stderr: "" };
+    // Tag command will default to ok:true via fallback
+    mockCommandResponses["rm -rf /home/user/.local/share/opencode/multi-model/test-session"] = { ok: true, stdout: "", stderr: "" };
+
+    // Freeze timestamp for deterministic tag name
+    const fixedDate = new Date("2023-01-01T00:00:00.000Z");
+    const OriginalDate = Date;
+    // @ts-ignore
+    global.Date = class extends OriginalDate { constructor() { super(); return fixedDate; } toISOString() { return "2023-01-01T00:00:00.000Z"; } } as any;
+
+    const result = await closeMultiModel({ sessionName: "test-session", cleanupWorktrees: true, force: true });
+    // Restore Date
+    // @ts-ignore
+    global.Date = OriginalDate;
+
+    expect(result.success).toBe(true);
+    expect(result.cleanupPerformed).toBe(true);
+    expect(result.worktreesRemoved).toEqual([worktreePath]);
+    expect(result.branchesDeleted).toEqual(["opencode/test-session/model"]);
+    expect(result.tagsCreated?.length).toBe(1);
+    expect(result.warnings).toEqual([]);
+    // Ensure removal commands were executed
+    expect(executedCommands).toContain(`git worktree remove -f ${worktreePath}`);
+    expect(executedCommands).toContain(`git branch -D opencode/test-session/model`);
+  });
+
+  test("user cancels cleanup when not forced", async () => {
+    mockCommandResponses["tmux has-session -t test-session"] = { ok: false, stdout: "", stderr: "" };
+    const worktreePath = "/home/user/.local/share/opencode/multi-model/test-session/model";
+    const worktreeListOutput = `worktree ${worktreePath}\nbranch refs/heads/opencode/test-session/model`;
+    mockCommandResponses["git worktree list --porcelain"] = { ok: true, stdout: worktreeListOutput, stderr: "" };
+
+    // Stub readline to return "n"
+    const mockInterface = {
+      question: (q: string, cb: (a: string) => void) => cb("n"),
+      close: () => {},
+    } as any;
+    spyOn(readline, "createInterface").mockImplementation(() => mockInterface);
+
+    const result = await closeMultiModel({ sessionName: "test-session", cleanupWorktrees: true, force: false });
+    expect(result.success).toBe(false);
+    expect(result.error).toBe("Cleanup cancelled by user");
+  });
+
+  test("warning when tag creation fails", async () => {
+    mockCommandResponses["tmux has-session -t test-session"] = { ok: false, stdout: "", stderr: "" };
+    const worktreePath = "/home/user/.local/share/opencode/multi-model/test-session/model";
+    const worktreeListOutput = `worktree ${worktreePath}\nbranch refs/heads/opencode/test-session/model`;
+    mockCommandResponses["git worktree list --porcelain"] = { ok: true, stdout: worktreeListOutput, stderr: "" };
+    mockCommandResponses[`git worktree remove -f ${worktreePath}`] = { ok: true, stdout: "", stderr: "" };
+    mockCommandResponses["git branch -D opencode/test-session/model"] = { ok: true, stdout: "", stderr: "" };
+    // Tag command will fail
+    const fixedDate = new Date("2023-01-01T00:00:00.000Z");
+    const OriginalDate = Date;
+    // @ts-ignore
+    global.Date = class extends OriginalDate { constructor() { super(); return fixedDate; } toISOString() { return "2023-01-01T00:00:00.000Z"; } } as any;
+    const tagCommand = `git tag archive/opencode/test-session/model-2023-01-01T00-00-00-000Z opencode/test-session/model`;
+    mockCommandResponses[tagCommand] = { ok: false, stdout: "", stderr: "tag error" };
+
+    const result = await closeMultiModel({ sessionName: "test-session", cleanupWorktrees: true, force: true });
+    // Restore Date
+    // @ts-ignore
+    global.Date = OriginalDate;
+
+    expect(result.success).toBe(true);
+    expect(result.warnings?.length).toBe(1);
+    expect(result.warnings?.[0]).toContain("Failed to create tag");
+    expect(result.tagsCreated).toEqual([]);
+  });
+
+  test("cleanup works with unsanitized session name", async () => {
+    const unsanitized = "test session!";
+    const sanitized = "test-session"; // result of sanitizeName
+    // tmux lookup uses unsanitized name
+    mockCommandResponses[`tmux has-session -t ${unsanitized}`] = { ok: false, stdout: "", stderr: "" };
+    const worktreePath = `/home/user/.local/share/opencode/multi-model/${sanitized}/model`;
+    const worktreeListOutput = `worktree ${worktreePath}\nbranch refs/heads/opencode/${sanitized}/model`;
+    mockCommandResponses["git worktree list --porcelain"] = { ok: true, stdout: worktreeListOutput, stderr: "" };
+    mockCommandResponses[`git worktree remove -f ${worktreePath}`] = { ok: true, stdout: "", stderr: "" };
+    mockCommandResponses[`git branch -D opencode/${sanitized}/model`] = { ok: true, stdout: "", stderr: "" };
+    mockCommandResponses[`rm -rf /home/user/.local/share/opencode/multi-model/${sanitized}`] = { ok: true, stdout: "", stderr: "" };
+
+    // Freeze timestamp for deterministic tag name
+    const fixedDate = new Date("2023-01-01T00:00:00.000Z");
+    const OriginalDate = Date;
+    // @ts-ignore
+    global.Date = class extends OriginalDate { constructor() { super(); return fixedDate; } toISOString() { return "2023-01-01T00:00:00.000Z"; } } as any;
+
+    const result = await closeMultiModel({ sessionName: unsanitized, cleanupWorktrees: true, force: true });
+    // Restore Date
+    // @ts-ignore
+    global.Date = OriginalDate;
+
+    expect(result.success).toBe(true);
+    expect(result.cleanupPerformed).toBe(true);
+    expect(result.worktreesRemoved).toEqual([worktreePath]);
+    expect(result.branchesDeleted).toEqual([`opencode/${sanitized}/model`]);
+    expect(result.tagsCreated?.length).toBe(1);
+    // Verify that the commands used the sanitized paths for worktree removal and branch deletion
+    expect(executedCommands).toContain(`git worktree remove -f ${worktreePath}`);
+    expect(executedCommands).toContain(`git branch -D opencode/${sanitized}/model`);
+  });
+});
diff --git a/tests/open.test.ts b/tests/open.test.ts
new file mode 100644
index 0000000..5be14ef
--- /dev/null
+++ b/tests/open.test.ts
@@ -0,0 +1,357 @@
+import { expect, test, mock, spyOn, beforeEach, afterEach, describe } from "bun:test";
+import * as fs from "node:fs";
+import * as os from "node:os";
+import { openMultiModel } from "../src/core/open";
+import {
+  shellQuote,
+  normalizeModels,
+  findDuplicates,
+  createWindowBaseName,
+  createWindowPlans,
+  levenshtein,
+  suggestModels,
+  formatInvalidModelError,
+  sanitizeName,
+  runCommand,
+  getWorktreePath,
+  getSessionPath,
+  undoWorktree,
+  launchModelInWindow,
+  getWorktreesForSession,
+  getBinaryName,
+} from "../src/core/utils";
+
+let originalBun$: typeof Bun.$ = (globalThis as any).Bun?.$;
+let mockCommandResponses: Record<string, { ok: boolean; stdout: string; stderr: string }> = {};
+let executedCommands: string[] = [];
+
+function setupMockBun$() {
+  const mockFn = mock((strings: TemplateStringsArray, ...values: any[]) => {
+    const parts = values[0] as string[];
+    const commandSignature = parts.join(" ");
+
+    executedCommands.push(commandSignature);
+
+    return {
+      quiet: () => ({
+        nothrow: async () => {
+          const response = mockCommandResponses[commandSignature] ?? { ok: true, stdout: "", stderr: "" };
+          return {
+            exitCode: response.ok ? 0 : 1,
+            stdout: { toString: () => response.stdout },
+            stderr: { toString: () => response.stderr },
+          };
+        },
+      }),
+    };
+  });
+
+  (globalThis as any).Bun.$ = mockFn;
+  return mockFn;
+}
+
+function restoreOriginalBun$() {
+  (globalThis as any).Bun.$ = originalBun$;
+}
+
+describe("multi-model launch", () => {
+  let existsSyncMock: ReturnType<typeof spyOn>;
+  let bunMock: ReturnType<typeof setupMockBun$>;
+
+  beforeEach(() => {
+    spyOn(os, "homedir").mockReturnValue("/mock/home");
+    existsSyncMock = spyOn(fs, "existsSync").mockReturnValue(false);
+    bunMock = setupMockBun$();
+    executedCommands = [];
+
+    mockCommandResponses = {
+      "git rev-parse --is-inside-work-tree": { ok: true, stdout: "true", stderr: "" },
+      "command -v tmux": { ok: true, stdout: "/usr/bin/tmux", stderr: "" },
+      "command -v opencode": { ok: true, stdout: "/usr/bin/opencode", stderr: "" },
+      "opencode models": { ok: true, stdout: "openai/gpt-5.2\nanthropic/claude-3-5-sonnet", stderr: "" },
+      "tmux has-session -t test-session": { ok: false, stdout: "", stderr: "session not found" },
+      "git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2": { ok: false, stdout: "", stderr: "" },
+    };
+  });
+
+  afterEach(() => {
+    restoreOriginalBun$();
+  });
+
+  test("fails if session name is empty", async () => {
+    const result = await openMultiModel({
+      sessionName: "",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Error: `sessionName` must not be empty.");
+    expect(executedCommands).toEqual([]);
+  });
+
+  test("fails if no models are provided", async () => {
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: [],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Error: Model names must not be empty.");
+    expect(executedCommands).toEqual([]);
+  });
+
+  test("fails if duplicate models are provided", async () => {
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2", "openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Duplicate model names are not allowed");
+    expect(executedCommands).toEqual([]);
+  });
+
+  test("fails if not inside a git repository", async () => {
+    mockCommandResponses["git rev-parse --is-inside-work-tree"] = { ok: false, stdout: "", stderr: "not a git repo" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Error: `multi-model` requires a git repository.");
+    expect(executedCommands).toEqual(["git rev-parse --is-inside-work-tree"]);
+  });
+
+  test("fails if tmux is not installed", async () => {
+    mockCommandResponses["command -v tmux"] = { ok: false, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Error: `tmux` is not installed or not on `PATH`.");
+    expect(executedCommands).toEqual([
+      "git rev-parse --is-inside-work-tree",
+      "command -v tmux",
+    ]);
+  });
+
+  test("fails if opencode is not installed", async () => {
+    mockCommandResponses["command -v opencode"] = { ok: false, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Error: `opencode` is not installed or not on `PATH`.");
+    expect(executedCommands).toEqual([
+      "git rev-parse --is-inside-work-tree",
+      "command -v tmux",
+      "command -v opencode",
+    ]);
+  });
+
+  test("fails if model name is not in allowlist", async () => {
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["invalid/model"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Error: Model name 'invalid/model' not found");
+    expect(executedCommands).toEqual([
+      "git rev-parse --is-inside-work-tree",
+      "command -v tmux",
+      "command -v opencode",
+      "opencode models",
+    ]);
+  });
+
+  test("fails if session already exists", async () => {
+    mockCommandResponses["tmux has-session -t test-session"] = { ok: true, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Error: Session already exists");
+    expect(executedCommands).toEqual([
+      "git rev-parse --is-inside-work-tree",
+      "command -v tmux",
+      "command -v opencode",
+      "opencode models",
+      "tmux has-session -t test-session",
+    ]);
+  });
+
+  test("successfully plans and executes tmux launch with single model", async () => {
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(true);
+    expect(result.instructions).toContain("Use `tmux attach -t test-session` to join session");
+    expect(executedCommands.some(c => c.startsWith("tmux new-session -d -s test-session -n gpt-5-2"))).toBe(true);
+    expect(executedCommands.some(c => c.startsWith("tmux send-keys -t test-session:gpt-5-2"))).toBe(true);
+  });
+
+  test("successfully launches multiple models", async () => {
+    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/claude-3-5-sonnet"] = { ok: false, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2", "anthropic/claude-3-5-sonnet"],
+    });
+
+    expect(result.success).toBe(true);
+    expect(result.instructions).toContain("Use `tmux attach -t test-session` to join session");
+    expect(executedCommands.some(c => c.startsWith("tmux new-session -d -s test-session -n gpt-5-2"))).toBe(true);
+    expect(executedCommands.some(c => c.startsWith("tmux new-window -d -t test-session -n claude-3-5-sonnet"))).toBe(true);
+  });
+
+  test("sanitizes session name", async () => {
+    mockCommandResponses["tmux has-session -t test session!"] = { ok: false, stdout: "", stderr: "" };
+    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2"] = { ok: false, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test session!",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(true);
+    expect(result.instructions).toContain("Use `tmux attach -t test session!` to join session");
+    expect(executedCommands.some(c => c.startsWith("git worktree add -b opencode/test-session/gpt-5-2"))).toBe(true);
+  });
+
+  test("fails if tmux new-session fails for the first model and triggers undo", async () => {
+    mockCommandResponses["tmux new-session -d -s test-session -n gpt-5-2 -c /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2"] = { ok: false, stdout: "", stderr: "tmux error" };
+    mockCommandResponses["git worktree remove -f /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2"] = { ok: true, stdout: "", stderr: "" };
+    mockCommandResponses["git branch -D opencode/test-session/gpt-5-2"] = { ok: true, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Failed to create tmux session");
+    expect(executedCommands).toEqual([
+      "git rev-parse --is-inside-work-tree",
+      "command -v tmux",
+      "command -v opencode",
+      "opencode models",
+      "tmux has-session -t test-session",
+      "git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2",
+      "git worktree add -b opencode/test-session/gpt-5-2 /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2",
+      "tmux new-session -d -s test-session -n gpt-5-2 -c /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2",
+      "git worktree remove -f /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2",
+      "git branch -D opencode/test-session/gpt-5-2",
+    ]);
+  });
+
+  test("fails if worktree path exists for first model", async () => {
+    existsSyncMock.mockImplementation((path: string) => {
+      return path.includes("test-session/gpt-5-2");
+    });
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Worktree path already exists");
+    expect(executedCommands).toEqual([
+      "git rev-parse --is-inside-work-tree",
+      "command -v tmux",
+      "command -v opencode",
+      "opencode models",
+      "tmux has-session -t test-session",
+    ]);
+  });
+
+  test("fails if git branch exists for first model", async () => {
+    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2"] = { ok: true, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Branch 'opencode/test-session/gpt-5-2' already exists");
+    expect(executedCommands).toEqual([
+      "git rev-parse --is-inside-work-tree",
+      "command -v tmux",
+      "command -v opencode",
+      "opencode models",
+      "tmux has-session -t test-session",
+      "git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2",
+    ]);
+  });
+
+  test("fails if git worktree add fails for first model", async () => {
+    mockCommandResponses["git worktree add -b opencode/test-session/gpt-5-2 /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2"] = { ok: false, stdout: "", stderr: "git error" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(false);
+    expect(result.error).toContain("Failed to create worktree");
+    expect(executedCommands).toEqual([
+      "git rev-parse --is-inside-work-tree",
+      "command -v tmux",
+      "command -v opencode",
+      "opencode models",
+      "tmux has-session -t test-session",
+      "git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2",
+      "git worktree add -b opencode/test-session/gpt-5-2 /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2",
+    ]);
+  });
+
+  test("model name collision creates unique window names", async () => {
+    mockCommandResponses["opencode models"] = { ok: true, stdout: "openai/gpt-5.2\nanthropic/gpt-5.2", stderr: "" };
+    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2"] = { ok: false, stdout: "", stderr: "" };
+    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2-2"] = { ok: false, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: ["openai/gpt-5.2", "anthropic/gpt-5.2"],
+    });
+
+    expect(result.success).toBe(true);
+    expect(result.instructions).toContain("Use `tmux attach -t test-session` to join session");
+    expect(executedCommands.some(c => c.startsWith("tmux new-session -d -s test-session -n gpt-5-2"))).toBe(true);
+    expect(executedCommands.some(c => c.startsWith("tmux new-window -d -t test-session -n gpt-5-2-2"))).toBe(true);
+  });
+
+  test("long model name is truncated in window name", async () => {
+    const longModel = "verylongmodelfrontexampleprovider";
+    mockCommandResponses["opencode models"] = { ok: true, stdout: longModel, stderr: "" };
+    mockCommandResponses[`git show-ref --verify --quiet refs/heads/opencode/test-session/${longModel.slice(0, 24)}`] = { ok: false, stdout: "", stderr: "" };
+
+    const result = await openMultiModel({
+      sessionName: "test-session",
+      models: [longModel],
+    });
+
+    expect(result.success).toBe(true);
+    expect(result.instructions).toContain("Use `tmux attach -t test-session` to join session");
+    const windowName = executedCommands.find(c => c.includes("tmux new-session"))?.match(/-n (\S+)/)?.[1];
+    expect(windowName?.length).toBeLessThanOrEqual(24);
+  });
+});
+
+// ----------
+// Core utils tests remain in a separate file.
diff --git a/tests/multi-model.test.ts b/tests/utils.test.ts
similarity index 54%
rename from tests/multi-model.test.ts
rename to tests/utils.test.ts
index 1f5e9b8..4443803 100644
--- a/tests/multi-model.test.ts
+++ b/tests/utils.test.ts
@@ -1,7 +1,6 @@
 import { expect, test, mock, spyOn, beforeEach, afterEach, describe } from "bun:test";
 import * as fs from "node:fs";
 import * as os from "node:os";
-import { openMultiModel } from "../src/core/open";
 import {
   shellQuote,
   normalizeModels,
@@ -29,9 +28,7 @@ function setupMockBun$() {
   const mockFn = mock((strings: TemplateStringsArray, ...values: any[]) => {
     const parts = values[0] as string[];
     const commandSignature = parts.join(" ");
-
     executedCommands.push(commandSignature);
-
     return {
       quiet: () => ({
         nothrow: async () => {
@@ -45,7 +42,6 @@ function setupMockBun$() {
       }),
     };
   });
-
   (globalThis as any).Bun.$ = mockFn;
   return mockFn;
 }
@@ -54,305 +50,6 @@ function restoreOriginalBun$() {
   (globalThis as any).Bun.$ = originalBun$;
 }
 
-describe("multi-model launch", () => {
-  let existsSyncMock: ReturnType<typeof spyOn>;
-  let bunMock: ReturnType<typeof setupMockBun$>;
-
-  beforeEach(() => {
-    spyOn(os, "homedir").mockReturnValue("/mock/home");
-    existsSyncMock = spyOn(fs, "existsSync").mockReturnValue(false);
-    bunMock = setupMockBun$();
-    executedCommands = [];
-
-    mockCommandResponses = {
-      "git rev-parse --is-inside-work-tree": { ok: true, stdout: "true", stderr: "" },
-      "command -v tmux": { ok: true, stdout: "/usr/bin/tmux", stderr: "" },
-      "command -v opencode": { ok: true, stdout: "/usr/bin/opencode", stderr: "" },
-      "opencode models": { ok: true, stdout: "openai/gpt-5.2\nanthropic/claude-3-5-sonnet", stderr: "" },
-      "tmux has-session -t test-session": { ok: false, stdout: "", stderr: "session not found" },
-      "git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2": { ok: false, stdout: "", stderr: "" },
-    };
-  });
-
-  afterEach(() => {
-    restoreOriginalBun$();
-  });
-
-  test("fails if session name is empty", async () => {
-    const result = await openMultiModel({
-      sessionName: "",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Error: `sessionName` must not be empty.");
-    expect(executedCommands).toEqual([]);
-  });
-
-  test("fails if no models are provided", async () => {
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: [],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Error: Model names must not be empty.");
-    expect(executedCommands).toEqual([]);
-  });
-
-  test("fails if duplicate models are provided", async () => {
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2", "openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Duplicate model names are not allowed");
-    expect(executedCommands).toEqual([]);
-  });
-
-  test("fails if not inside a git repository", async () => {
-    mockCommandResponses["git rev-parse --is-inside-work-tree"] = { ok: false, stdout: "", stderr: "not a git repo" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Error: `multi-model` requires a git repository.");
-    expect(executedCommands).toEqual(["git rev-parse --is-inside-work-tree"]);
-  });
-
-  test("fails if tmux is not installed", async () => {
-    mockCommandResponses["command -v tmux"] = { ok: false, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Error: `tmux` is not installed or not on `PATH`.");
-    expect(executedCommands).toEqual([
-      "git rev-parse --is-inside-work-tree",
-      "command -v tmux"
-    ]);
-  });
-
-  test("fails if opencode is not installed", async () => {
-    mockCommandResponses["command -v opencode"] = { ok: false, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Error: `opencode` is not installed or not on `PATH`.");
-    expect(executedCommands).toEqual([
-      "git rev-parse --is-inside-work-tree",
-      "command -v tmux",
-      "command -v opencode"
-    ]);
-  });
-
-  test("fails if model name is not in allowlist", async () => {
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["invalid/model"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Error: Model name 'invalid/model' not found");
-    expect(executedCommands).toEqual([
-      "git rev-parse --is-inside-work-tree",
-      "command -v tmux",
-      "command -v opencode",
-      "opencode models"
-    ]);
-  });
-
-  test("fails if session already exists", async () => {
-    mockCommandResponses["tmux has-session -t test-session"] = { ok: true, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Error: Session already exists");
-    expect(executedCommands).toEqual([
-      "git rev-parse --is-inside-work-tree",
-      "command -v tmux",
-      "command -v opencode",
-      "opencode models",
-      "tmux has-session -t test-session"
-    ]);
-  });
-
-  test("successfully plans and executes tmux launch with single model", async () => {
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(true);
-    expect(result.instructions).toContain("Use `tmux attach -t test-session` to join session");
-    expect(executedCommands.some(c => c.startsWith("tmux new-session -d -s test-session -n gpt-5-2"))).toBe(true);
-    expect(executedCommands.some(c => c.startsWith("tmux send-keys -t test-session:gpt-5-2"))).toBe(true);
-  });
-
-  test("successfully launches multiple models", async () => {
-    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/claude-3-5-sonnet"] = { ok: false, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2", "anthropic/claude-3-5-sonnet"],
-    });
-
-    expect(result.success).toBe(true);
-    expect(result.instructions).toContain("Use `tmux attach -t test-session` to join session");
-    expect(executedCommands.some(c => c.startsWith("tmux new-session -d -s test-session -n gpt-5-2"))).toBe(true);
-    expect(executedCommands.some(c => c.startsWith("tmux new-window -d -t test-session -n claude-3-5-sonnet"))).toBe(true);
-  });
-
-  test("sanitizes session name", async () => {
-    mockCommandResponses["tmux has-session -t test session!"] = { ok: false, stdout: "", stderr: "" };
-    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2"] = { ok: false, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test session!",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(true);
-    expect(result.instructions).toContain("Use `tmux attach -t test session!` to join session");
-    expect(executedCommands.some(c => c.startsWith("git worktree add -b opencode/test-session/gpt-5-2"))).toBe(true);
-  });
-
-  test("fails if tmux new-session fails for the first model and triggers undo", async () => {
-    mockCommandResponses["tmux new-session -d -s test-session -n gpt-5-2 -c /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2"] = { ok: false, stdout: "", stderr: "tmux error" };
-    mockCommandResponses["git worktree remove -f /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2"] = { ok: true, stdout: "", stderr: "" };
-    mockCommandResponses["git branch -D opencode/test-session/gpt-5-2"] = { ok: true, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Failed to create tmux session");
-    expect(executedCommands).toEqual([
-      "git rev-parse --is-inside-work-tree",
-      "command -v tmux",
-      "command -v opencode",
-      "opencode models",
-      "tmux has-session -t test-session",
-      "git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2",
-      "git worktree add -b opencode/test-session/gpt-5-2 /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2",
-      "tmux new-session -d -s test-session -n gpt-5-2 -c /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2",
-      "git worktree remove -f /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2",
-      "git branch -D opencode/test-session/gpt-5-2"
-    ]);
-  });
-
-  test("fails if worktree path exists for first model", async () => {
-    existsSyncMock.mockImplementation((path: string) => {
-      return path.includes("test-session/gpt-5-2");
-    });
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Worktree path already exists");
-    expect(executedCommands).toEqual([
-      "git rev-parse --is-inside-work-tree",
-      "command -v tmux",
-      "command -v opencode",
-      "opencode models",
-      "tmux has-session -t test-session"
-    ]);
-  });
-
-  test("fails if git branch exists for first model", async () => {
-    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2"] = { ok: true, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Branch 'opencode/test-session/gpt-5-2' already exists");
-    expect(executedCommands).toEqual([
-      "git rev-parse --is-inside-work-tree",
-      "command -v tmux",
-      "command -v opencode",
-      "opencode models",
-      "tmux has-session -t test-session",
-      "git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2"
-    ]);
-  });
-
-  test("fails if git worktree add fails for first model", async () => {
-    mockCommandResponses["git worktree add -b opencode/test-session/gpt-5-2 /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2"] = { ok: false, stdout: "", stderr: "git error" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(false);
-    expect(result.error).toContain("Failed to create worktree");
-    expect(executedCommands).toEqual([
-      "git rev-parse --is-inside-work-tree",
-      "command -v tmux",
-      "command -v opencode",
-      "opencode models",
-      "tmux has-session -t test-session",
-      "git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2",
-      "git worktree add -b opencode/test-session/gpt-5-2 /mock/home/.local/share/opencode/multi-model/test-session/gpt-5-2"
-    ]);
-  });
-
-  test("model name collision creates unique window names", async () => {
-    mockCommandResponses["opencode models"] = { ok: true, stdout: "openai/gpt-5.2\nanthropic/gpt-5.2", stderr: "" };
-    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2"] = { ok: false, stdout: "", stderr: "" };
-    mockCommandResponses["git show-ref --verify --quiet refs/heads/opencode/test-session/gpt-5-2-2"] = { ok: false, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: ["openai/gpt-5.2", "anthropic/gpt-5.2"],
-    });
-
-    expect(result.success).toBe(true);
-    expect(result.instructions).toContain("Use `tmux attach -t test-session` to join session");
-    expect(executedCommands.some(c => c.startsWith("tmux new-session -d -s test-session -n gpt-5-2"))).toBe(true);
-    expect(executedCommands.some(c => c.startsWith("tmux new-window -d -t test-session -n gpt-5-2-2"))).toBe(true);
-  });
-
-  test("long model name is truncated in window name", async () => {
-    const longModel = "verylongmodelfrontexampleprovider";
-    mockCommandResponses["opencode models"] = { ok: true, stdout: longModel, stderr: "" };
-    mockCommandResponses[`git show-ref --verify --quiet refs/heads/opencode/test-session/${longModel.slice(0, 24)}`] = { ok: false, stdout: "", stderr: "" };
-
-    const result = await openMultiModel({
-      sessionName: "test-session",
-      models: [longModel],
-    });
-
-    expect(result.success).toBe(true);
-    expect(result.instructions).toContain("Use `tmux attach -t test-session` to join session");
-    const windowName = executedCommands.find(c => c.includes("tmux new-session"))?.match(/-n (\S+)/)?.[1];
-    expect(windowName?.length).toBeLessThanOrEqual(24);
-  });
-});
-
 describe("core utils", () => {
   let bunMock: ReturnType<typeof setupMockBun$>;
 
@@ -371,19 +68,15 @@ describe("core utils", () => {
     test("normal string without special characters", () => {
       expect(shellQuote("test")).toBe("'test'");
     });
-
     test("string with spaces", () => {
       expect(shellQuote("test value")).toBe("'test value'");
     });
-
     test("string with single quotes", () => {
       expect(shellQuote("test'value")).toBe("'test'\"'\"'value'");
     });
-
     test("string with multiple single quotes", () => {
       expect(shellQuote("te's't'v'alue")).toBe("'te'\"'\"'s'\"'\"'t'\"'\"'v'\"'\"'alue'");
     });
-
     test("empty string", () => {
       expect(shellQuote("")).toBe("''");
     });
@@ -393,15 +86,12 @@ describe("core utils", () => {
     test("empty array", () => {
       expect(normalizeModels([])).toEqual([]);
     });
-
     test("undefined input", () => {
       expect(normalizeModels(undefined)).toEqual([]);
     });
-
     test("array with whitespace-only strings", () => {
       expect(normalizeModels(["   ", "  "])).toEqual([]);
     });
-
     test("array with mixed valid models, padded models, and empty strings", () => {
       expect(normalizeModels([" openai/gpt-5.2 ", "", " anthropic/claude "])).toEqual(["openai/gpt-5.2", "anthropic/claude"]);
     });
@@ -411,19 +101,15 @@ describe("core utils", () => {
     test("array with no duplicates", () => {
       expect(findDuplicates(["a", "b", "c"])).toEqual([]);
     });
-
     test("array with one duplicate pair", () => {
       expect(findDuplicates(["a", "b", "a"])).toEqual(["a"]);
     });
-
     test("array with multiple different duplicates", () => {
       expect(findDuplicates(["a", "b", "a", "c", "b"])).toEqual(["a", "b"]);
     });
-
     test("array with a single value repeated more than twice", () => {
       expect(findDuplicates(["a", "a", "a"])).toEqual(["a"]);
     });
-
     test("verifying first-repeated-occurrence order", () => {
       expect(findDuplicates(["x", "a", "b", "a", "x", "b"])).toEqual(["a", "x", "b"]);
     });
@@ -433,20 +119,16 @@ describe("core utils", () => {
     test("normal model name without slashes", () => {
       expect(createWindowBaseName("gpt-5-2")).toBe("gpt-5-2");
     });
-
     test("model with slashes", () => {
       expect(createWindowBaseName("vendor/namespace/model")).toBe("model");
     });
-
     test("model exceeding WINDOW_NAME_LIMIT", () => {
       const longName = "a".repeat(30);
       expect(createWindowBaseName(longName)).toBe("aaaaaaaaaaaaaaaaaaaaaaaa");
     });
-
     test("model with special characters", () => {
       expect(createWindowBaseName("OpenAI/GPT_4.0!")).toBe("gpt-4-0");
     });
-
     test("model made entirely of special characters", () => {
       expect(createWindowBaseName("!@#$%^&*()")).toBe("model");
     });
@@ -456,21 +138,18 @@ describe("core utils", () => {
     test("single model", () => {
       expect(createWindowPlans(["openai/gpt-5-2"])).toEqual([{ model: "openai/gpt-5-2", windowName: "gpt-5-2" }]);
     });
-
     test("two models with the same base name", () => {
       expect(createWindowPlans(["openai/gpt-5-2", "anthropic/gpt-5-2"])).toEqual([
         { model: "openai/gpt-5-2", windowName: "gpt-5-2" },
-        { model: "anthropic/gpt-5-2", windowName: "gpt-5-2-2" }
+        { model: "anthropic/gpt-5-2", windowName: "gpt-5-2-2" },
       ]);
     });
-
     test("multiple collisions", () => {
       const result = createWindowPlans(["a", "b", "c", "a", "b", "a"]);
       expect(result[0]?.windowName).toBe("a");
       expect(result[3]?.windowName).toBe("a-2");
       expect(result[5]?.windowName).toBe("a-3");
     });
-
     test("truncation to accommodate suffix", () => {
       const longBase = "a".repeat(23);
       const result = createWindowPlans([longBase, "b"]);
@@ -482,27 +161,21 @@ describe("core utils", () => {
     test("identical strings", () => {
       expect(levenshtein("test", "test")).toBe(0);
     });
-
     test("one substitution", () => {
       expect(levenshtein("test", "tent")).toBe(1);
     });
-
     test("one insertion", () => {
       expect(levenshtein("test", "tests")).toBe(1);
     });
-
     test("one deletion", () => {
       expect(levenshtein("tests", "test")).toBe(1);
     });
-
     test("completely different strings", () => {
       expect(levenshtein("abc", "xyz")).toBe(3);
     });
-
     test("one empty string", () => {
       expect(levenshtein("", "test")).toBe(4);
     });
-
     test("both empty strings", () => {
       expect(levenshtein("", "")).toBe(0);
     });
@@ -513,21 +186,17 @@ describe("core utils", () => {
       const result = suggestModels("gpt-5.2", ["gpt-5.2", "gpt-5.2-mini"]);
       expect(result[0]).toBe("gpt-5.2");
     });
-
     test("fuzzy match/typo", () => {
       expect(suggestModels("gpt5.4", ["gpt-5.4"])).toEqual(["gpt-5.4"]);
     });
-
     test("fuzzy match with contains boost", () => {
       const suggestions = suggestModels("gpt4o", ["gpt-5.2", "gpt-5.2-mini"]);
       expect(suggestions[0]).toBe("gpt-5.2");
     });
-
     test("maximum of 3 suggestions", () => {
       const allowlist = ["gpt-5.2", "gpt-5.2-mini", "gpt-5.2-pro", "gpt-5.2-ultra"];
       expect(suggestModels("gpt4o", allowlist).length).toBe(3);
     });
-
     test("sorting logic", () => {
       const suggestions = suggestModels("abc", ["abc", "abd", "abe"]);
       expect(suggestions).toEqual(["abc", "abd", "abe"]);
@@ -540,13 +209,11 @@ describe("core utils", () => {
       expect(error).toContain("Model name 'gpt5.4' not found");
       expect(error).toContain("Did you mean");
     });
-
     test("single invalid model without close matches", () => {
       const error = formatInvalidModelError(["xyz"], ["abc", "def"]);
       expect(error).toContain("Model name 'xyz' not found");
       expect(error).toContain("Did you mean");
     });
-
     test("multiple invalid models", () => {
       const error = formatInvalidModelError(["xyz", "abc"], ["def"]);
       expect(error).toContain("Model names not found");
@@ -559,15 +226,12 @@ describe("core utils", () => {
     test("normal alphanumeric name", () => {
       expect(sanitizeName("test-session")).toBe("test-session");
     });
-
     test("name with spaces and special chars", () => {
       expect(sanitizeName("test session!")).toBe("test-session");
     });
-
     test("name with consecutive hyphens", () => {
       expect(sanitizeName("test--session")).toBe("test-session");
     });
-
     test("name with leading/trailing hyphens", () => {
       expect(sanitizeName("-test-session-")).toBe("test-session");
     });
@@ -581,7 +245,6 @@ describe("core utils", () => {
       expect(result.stdout).toBe("hello");
       expect(result.stderr).toBe("");
     });
-
     test("returns ok false for failed command", async () => {
       mockCommandResponses["false"] = { ok: false, stdout: "", stderr: "error" };
       const result = await runCommand(["false"]);
@@ -596,7 +259,6 @@ describe("core utils", () => {
       const result = getWorktreePath("my-session", "gpt-5.2");
       expect(result).toBe("/home/user/.local/share/opencode/multi-model/my-session/gpt-5.2");
     });
-
     test("handles nested session names", () => {
       spyOn(os, "homedir").mockReturnValue("/home/user");
       const result = getWorktreePath("parent/child", "window");
@@ -620,7 +282,6 @@ describe("core utils", () => {
       const errors = await undoWorktree("/path/to/worktree", "opencode/session/window");
       expect(errors).toEqual([]);
     });
-
     test("returns error when worktree remove fails", async () => {
       mockCommandResponses["git worktree remove -f /path/to/worktree"] = { ok: false, stdout: "", stderr: "remove failed" };
       mockCommandResponses["git branch -D opencode/session/window"] = { ok: true, stdout: "", stderr: "" };
@@ -629,7 +290,6 @@ describe("core utils", () => {
       expect(errors.length).toBe(1);
       expect(errors[0]).toContain("Failed to remove worktree");
     });
-
     test("returns error when branch delete fails", async () => {
       mockCommandResponses["git worktree remove -f /path/to/worktree"] = { ok: true, stdout: "", stderr: "" };
       mockCommandResponses["git branch -D opencode/session/window"] = { ok: false, stdout: "", stderr: "branch delete failed" };
@@ -638,7 +298,6 @@ describe("core utils", () => {
       expect(errors.length).toBe(1);
       expect(errors[0]).toContain("Failed to delete branch");
     });
-
     test("returns both errors when both operations fail", async () => {
       mockCommandResponses["git worktree remove -f /path/to/worktree"] = { ok: false, stdout: "", stderr: "remove failed" };
       mockCommandResponses["git branch -D opencode/session/window"] = { ok: false, stdout: "", stderr: "branch delete failed" };
@@ -656,7 +315,6 @@ describe("core utils", () => {
       expect(result.ok).toBe(true);
       expect(executedCommands).toContain("tmux send-keys -t session:window opencode --model 'openai/gpt-5.2' C-m");
     });
-
     test("uses custom binary name", async () => {
       mockCommandResponses["tmux send-keys -t session:window kilo --model 'openai/gpt-5.2' C-m"] = { ok: true, stdout: "", stderr: "" };
 
@@ -680,23 +338,18 @@ describe("core utils", () => {
       expect(worktrees[0]?.path).toBe("/home/user/.local/share/opencode/multi-model/my-session/gpt-5.2");
       expect(worktrees[0]?.branch).toBe("opencode/my-session/gpt-5.2");
     });
-
     test("sanitizes session name when filtering worktrees", async () => {
       spyOn(os, "homedir").mockReturnValue("/home/user");
-      // The worktree path uses the sanitized version "my-session"
       mockCommandResponses["git worktree list --porcelain"] = {
         ok: true,
         stdout: "worktree /home/user/.local/share/opencode/multi-model/my-session/gpt-5.2\nbranch refs/heads/opencode/my-session/gpt-5.2",
         stderr: "",
       };
 
-      // Pass unsanitized session name with spaces and special chars
       const worktrees = await getWorktreesForSession("my session!");
-      // Should still find the worktree because it sanitizes internally
       expect(worktrees.length).toBe(1);
       expect(worktrees[0]?.path).toBe("/home/user/.local/share/opencode/multi-model/my-session/gpt-5.2");
     });
-
     test("returns empty array when no matching worktrees", async () => {
       spyOn(os, "homedir").mockReturnValue("/home/user");
       mockCommandResponses["git worktree list --porcelain"] = {
@@ -715,7 +368,6 @@ describe("core utils", () => {
       delete process.env.OPENCODE_MULTI_MODEL_BINARY;
       expect(getBinaryName()).toBe("opencode");
     });
-
     test("returns env var value when set", () => {
       process.env.OPENCODE_MULTI_MODEL_BINARY = "kilo";
       expect(getBinaryName()).toBe("kilo");