diff --git a/bun.lock b/bun.lock
index 2aa72ea94af..5bb303e5a40 100644
--- a/bun.lock
+++ b/bun.lock
@@ -190,9 +190,11 @@
       "dependencies": {
         "@opencode-ai/app": "workspace:*",
         "@opencode-ai/ui": "workspace:*",
+        "@opencode-ai/util": "workspace:*",
         "@solid-primitives/i18n": "2.2.1",
         "@solid-primitives/storage": "catalog:",
         "@solidjs/meta": "catalog:",
+        "@solidjs/router": "catalog:",
         "@tauri-apps/api": "^2",
         "@tauri-apps/plugin-clipboard-manager": "~2",
         "@tauri-apps/plugin-deep-link": "~2",
diff --git a/packages/app/src/app.tsx b/packages/app/src/app.tsx
index e370862212b..cf010c92620 100644
--- a/packages/app/src/app.tsx
+++ b/packages/app/src/app.tsx
@@ -56,13 +56,16 @@ const HomeRoute = () => (
   </Suspense>
 )
 
-const SessionRoute = () => (
-  <SessionProviders>
-    <Suspense fallback={<Loading />}>
-      <Session />
-    </Suspense>
-  </SessionProviders>
-)
+function SessionRoute(props: { sessionChildren?: JSX.Element }) {
+  return (
+    <SessionProviders>
+      {props.sessionChildren}
+      <Suspense fallback={<Loading />}>
+        <Session />
+      </Suspense>
+    </SessionProviders>
+  )
+}
 
 const SessionIndexRoute = () => <Navigate href="session" />
 
@@ -271,6 +274,7 @@ export function AppInterface(props: {
   servers?: Array<ServerConnection.Any>
   router?: Component<BaseRouterProps>
   disableHealthCheck?: boolean
+  sessionChildren?: JSX.Element
 }) {
   return (
     <ServerProvider defaultServer={props.defaultServer} servers={props.servers}>
@@ -284,7 +288,10 @@ export function AppInterface(props: {
               <Route path="/" component={HomeRoute} />
               <Route path="/:dir" component={DirectoryLayout}>
                 <Route path="/" component={SessionIndexRoute} />
-                <Route path="/session/:id?" component={SessionRoute} />
+                <Route
+                  path="/session/:id?"
+                  component={() => <SessionRoute sessionChildren={props.sessionChildren} />}
+                />
               </Route>
             </Dynamic>
           </GlobalSyncProvider>
diff --git a/packages/app/src/i18n/en.ts b/packages/app/src/i18n/en.ts
index 7f6816de9e3..0c1b3112a9b 100644
--- a/packages/app/src/i18n/en.ts
+++ b/packages/app/src/i18n/en.ts
@@ -81,6 +81,8 @@ export const dict = {
   "command.session.redo.description": "Redo the last undone message",
   "command.session.compact": "Compact session",
   "command.session.compact.description": "Summarize the session to reduce context size",
+  "command.session.duplicate": "Duplicate session",
+  "command.session.duplicate.description": "Create a new chat with the current session history",
   "command.session.fork": "Fork from message",
   "command.session.fork.description": "Create a new session from a previous message",
   "command.session.share": "Share session",
diff --git a/packages/app/src/index.ts b/packages/app/src/index.ts
index 6c870dfa4d0..d2baaa96416 100644
--- a/packages/app/src/index.ts
+++ b/packages/app/src/index.ts
@@ -1,5 +1,8 @@
 export { AppBaseProviders, AppInterface } from "./app"
 export { useCommand } from "./context/command"
+export { useLanguage } from "./context/language"
 export { type DisplayBackend, type Platform, PlatformProvider } from "./context/platform"
+export { usePrompt } from "./context/prompt"
+export { useSDK } from "./context/sdk"
 export { ServerConnection } from "./context/server"
 export { handleNotificationClick } from "./utils/notification-click"
diff --git a/packages/desktop/package.json b/packages/desktop/package.json
index 73ec5278f6e..64709645a3e 100644
--- a/packages/desktop/package.json
+++ b/packages/desktop/package.json
@@ -15,8 +15,10 @@
   "dependencies": {
     "@opencode-ai/app": "workspace:*",
     "@opencode-ai/ui": "workspace:*",
+    "@opencode-ai/util": "workspace:*",
     "@solid-primitives/i18n": "2.2.1",
     "@solid-primitives/storage": "catalog:",
+    "@solidjs/router": "catalog:",
     "@tauri-apps/api": "^2",
     "@tauri-apps/plugin-clipboard-manager": "~2",
     "@tauri-apps/plugin-deep-link": "~2",
diff --git a/packages/desktop/src/duplicate-command.ts b/packages/desktop/src/duplicate-command.ts
new file mode 100644
index 00000000000..a0eabced98b
--- /dev/null
+++ b/packages/desktop/src/duplicate-command.ts
@@ -0,0 +1,73 @@
+import { base64Encode } from "@opencode-ai/util/encode"
+
+type Fork = { data?: { id: string } | null }
+
+export type State = {
+  current(): unknown
+  cursor(): number | undefined
+  set(value: unknown, cursor?: number, scope?: unknown): void
+}
+
+export type SDK = {
+  directory: string
+  client: {
+    session: {
+      fork: (opts: { sessionID: string }) => Promise<Fork>
+    }
+  }
+}
+
+export function duplicateSession(opts: {
+  id?: string
+  t: (key: string) => string
+  prompt: State
+  sdk: SDK
+  navigate: (href: string) => void
+  toast: (opts: { title: string; description?: string }) => void
+  frame: (cb: FrameRequestCallback) => void
+}) {
+  if (!opts.id) return Promise.resolve()
+
+  const value = opts.prompt.current()
+  const cursor = opts.prompt.cursor()
+  const dir = base64Encode(opts.sdk.directory)
+
+  return opts.sdk.client.session
+    .fork({ sessionID: opts.id })
+    .then((result: Fork) => {
+      if (!result.data) {
+        opts.toast({ title: opts.t("common.requestFailed") })
+        return
+      }
+
+      opts.navigate(`/${dir}/session/${result.data.id}`)
+      opts.frame(() => {
+        opts.prompt.set(value, cursor)
+      })
+    })
+    .catch((err: unknown) => {
+      opts.toast({
+        title: opts.t("common.requestFailed"),
+        description: err instanceof Error ? err.message : String(err),
+      })
+    })
+}
+
+export function duplicateCommand(opts: {
+  id?: string
+  t: (key: string) => string
+  prompt: State
+  sdk: SDK
+  navigate: (href: string) => void
+  toast: (opts: { title: string; description?: string }) => void
+  frame: (cb: FrameRequestCallback) => void
+}) {
+  return {
+    id: "desktop.session.duplicate",
+    title: opts.t("command.session.duplicate"),
+    description: opts.t("command.session.duplicate.description"),
+    slash: "duplicate",
+    disabled: !opts.id,
+    onSelect: () => duplicateSession(opts),
+  }
+}
diff --git a/packages/desktop/src/duplicate.test.ts b/packages/desktop/src/duplicate.test.ts
new file mode 100644
index 00000000000..50ccb3d4c32
--- /dev/null
+++ b/packages/desktop/src/duplicate.test.ts
@@ -0,0 +1,104 @@
+import { describe, expect, mock, test } from "bun:test"
+import { base64Encode } from "@opencode-ai/util/encode"
+import { duplicateCommand, duplicateSession } from "./duplicate-command"
+
+function state() {
+  return {
+    current: () => [{ type: "text", content: "draft" }],
+    cursor: () => 3,
+    set: mock(() => {}),
+  }
+}
+
+function sdk(result: Promise<{ data?: { id: string } | null }>) {
+  const fork = mock(() => result)
+  return {
+    fork,
+    value: {
+      directory: "/tmp/work",
+      client: {
+        session: { fork },
+      },
+    },
+  }
+}
+
+describe("duplicate command", () => {
+  test("disables the slash command without a session id", () => {
+    const prompt = state()
+    const cmd = duplicateCommand({
+      t: (key) => key,
+      prompt,
+      sdk: sdk(Promise.resolve({ data: { id: "next" } })).value,
+      navigate: mock(() => {}),
+      toast: mock(() => {}),
+      frame: (cb) => void cb(0),
+    })
+
+    expect(cmd.disabled).toBe(true)
+    expect(cmd.slash).toBe("duplicate")
+  })
+
+  test("forks the session, navigates, and restores the draft", async () => {
+    const prompt = state()
+    const nav = mock(() => {})
+    const toast = mock(() => {})
+    const api = sdk(Promise.resolve({ data: { id: "next" } }))
+    const frame = mock((cb: FrameRequestCallback) => void cb(0))
+
+    await duplicateSession({
+      id: "sess-1",
+      t: (key) => key,
+      prompt,
+      sdk: api.value,
+      navigate: nav,
+      toast,
+      frame,
+    })
+
+    expect(api.fork).toHaveBeenCalledWith({ sessionID: "sess-1" })
+    expect(nav).toHaveBeenCalledWith(`/${base64Encode("/tmp/work")}/session/next`)
+    expect(frame).toHaveBeenCalledTimes(1)
+    expect(prompt.set).toHaveBeenCalledWith([{ type: "text", content: "draft" }], 3)
+    expect(toast).not.toHaveBeenCalled()
+  })
+
+  test("shows a failure toast when the fork response is empty", async () => {
+    const prompt = state()
+    const nav = mock(() => {})
+    const toast = mock(() => {})
+
+    await duplicateSession({
+      id: "sess-1",
+      t: (key) => key,
+      prompt,
+      sdk: sdk(Promise.resolve({ data: null })).value,
+      navigate: nav,
+      toast,
+      frame: (cb) => void cb(0),
+    })
+
+    expect(nav).not.toHaveBeenCalled()
+    expect(prompt.set).not.toHaveBeenCalled()
+    expect(toast).toHaveBeenCalledWith({ title: "common.requestFailed" })
+  })
+
+  test("shows the thrown error message when the fork request fails", async () => {
+    const toast = mock(() => {})
+
+    await duplicateSession({
+      id: "sess-1",
+      t: (key) => key,
+      prompt: state(),
+      sdk: sdk(Promise.reject(new Error("boom"))).value,
+      navigate: mock(() => {}),
+      toast,
+      frame: (cb) => void cb(0),
+    })
+
+    expect(toast).toHaveBeenCalledWith({
+      title: "common.requestFailed",
+      description: "boom",
+    })
+  })
+})
diff --git a/packages/desktop/src/duplicate.tsx b/packages/desktop/src/duplicate.tsx
new file mode 100644
index 00000000000..6168f87a833
--- /dev/null
+++ b/packages/desktop/src/duplicate.tsx
@@ -0,0 +1,27 @@
+import { useCommand, useLanguage, usePrompt, useSDK } from "@opencode-ai/app"
+import { showToast } from "@opencode-ai/ui/toast"
+import { useNavigate, useParams } from "@solidjs/router"
+import { duplicateCommand } from "./duplicate-command"
+
+export function Duplicate() {
+  const command = useCommand()
+  const params = useParams()
+  const navigate = useNavigate()
+  const language = useLanguage()
+  const prompt = usePrompt()
+  const sdk = useSDK()
+
+  command.register("desktop.session.duplicate", () => [
+    duplicateCommand({
+      id: params.id,
+      t: language.t,
+      prompt,
+      sdk,
+      navigate,
+      toast: showToast,
+      frame: requestAnimationFrame,
+    }),
+  ])
+
+  return null
+}
diff --git a/packages/desktop/src/index.tsx b/packages/desktop/src/index.tsx
index 65149f34bc1..c1a517589bb 100644
--- a/packages/desktop/src/index.tsx
+++ b/packages/desktop/src/index.tsx
@@ -31,6 +31,7 @@ import "./styles.css"
 import { Channel } from "@tauri-apps/api/core"
 import { commands, type InitStep } from "./bindings"
 import { createMenu } from "./menu"
+import { Duplicate } from "./duplicate"
 
 const root = document.getElementById("root")
 if (import.meta.env.DEV && !(root instanceof HTMLElement)) {
@@ -469,6 +470,7 @@ render(() => {
               <AppInterface
                 defaultServer={defaultServer.latest ?? ServerConnection.Key.make("sidecar")}
                 servers={servers()}
+                sessionChildren={<Duplicate />}
               >
                 <Inner />
               </AppInterface>
diff --git a/packages/desktop/tsconfig.json b/packages/desktop/tsconfig.json
index 47e63cc87ff..9ef0f12470c 100644
--- a/packages/desktop/tsconfig.json
+++ b/packages/desktop/tsconfig.json
@@ -12,11 +12,13 @@
     "resolveJsonModule": true,
     "strict": true,
     "isolatedModules": true,
+    "disableSourceOfProjectReferenceRedirect": true,
     "noEmit": true,
     "emitDeclarationOnly": false,
     "outDir": "node_modules/.ts-dist",
     "types": ["vite/client"]
   },
-  "references": [{ "path": "../app" }],
-  "include": ["src", "package.json"]
+  "references": [{ "path": "../app" }, { "path": "../sdk/js" }],
+  "include": ["src", "package.json"],
+  "exclude": ["src/**/*.test.ts"]
 }
diff --git a/packages/web/src/content/docs/commands.mdx b/packages/web/src/content/docs/commands.mdx
index 1d7e4f1c21a..a95c4ed42ba 100644
--- a/packages/web/src/content/docs/commands.mdx
+++ b/packages/web/src/content/docs/commands.mdx
@@ -9,7 +9,7 @@ Custom commands let you specify a prompt you want to run when that command is ex
 /my-command
 ```
 
-Custom commands are in addition to the built-in commands like `/init`, `/undo`, `/redo`, `/share`, `/help`. [Learn more](/docs/tui#commands).
+Custom commands are in addition to the built-in commands like `/init`, `/undo`, `/redo`, `/share`, `/help`. On desktop, `/duplicate` is also available to clone the current session into a new chat. [Learn more](/docs/tui#commands).
 
 ---