diff --git a/src/commands/audit.ts b/src/commands/audit.ts
index a6f693f..830f2b4 100644
--- a/src/commands/audit.ts
+++ b/src/commands/audit.ts
@@ -351,7 +351,7 @@ export const audit = async (args: string[], flags: Flags) => {
 
   await new Promise(r => setTimeout(r, 300))
   await cdp.cleanup()
-  close()
+  await close()
 
   const { contrast, browser } = cdp
   const headingSkips = findHeadingSkips(data.a11y.headings)
diff --git a/src/commands/back.ts b/src/commands/back.ts
index 90e316b..22a9c87 100644
--- a/src/commands/back.ts
+++ b/src/commands/back.ts
@@ -5,5 +5,5 @@ export const back = async (args: string[], flags: Flags) => {
   const { page, close } = await connect(flags.tab)
   await page.goBack({ waitUntil: "domcontentloaded", timeout: flags.timeout })
   console.log(page.url())
-  close()
+  await close()
 }
diff --git a/src/commands/click.ts b/src/commands/click.ts
index 4ace635..7acb24d 100644
--- a/src/commands/click.ts
+++ b/src/commands/click.ts
@@ -20,5 +20,5 @@ export const click = async (args: string[], flags: Flags) => {
     button: flags.right ? "right" : "left",
     clickCount: flags.double ? 2 : 1,
   })
-  close()
+  await close()
 }
diff --git a/src/commands/drag.ts b/src/commands/drag.ts
index 709cda7..6d16407 100644
--- a/src/commands/drag.ts
+++ b/src/commands/drag.ts
@@ -21,5 +21,5 @@ export const drag = async (args: string[], flags: Flags) => {
   await page.mouse.move(x2!, y2!, { steps: 10 })
   await page.mouse.up()
 
-  close()
+  await close()
 }
diff --git a/src/commands/fill.ts b/src/commands/fill.ts
index aee2308..1140a73 100644
--- a/src/commands/fill.ts
+++ b/src/commands/fill.ts
@@ -122,7 +122,7 @@ export const fill = async (args: string[], flags: Flags) => {
     return { filled, failed }
   }, fields)
 
-  close()
+  await close()
 
   if (results.filled.length > 0) {
     console.log(`Filled: ${results.filled.join(", ")}`)
diff --git a/src/commands/forward.ts b/src/commands/forward.ts
index d7a8595..0ea0598 100644
--- a/src/commands/forward.ts
+++ b/src/commands/forward.ts
@@ -5,5 +5,5 @@ export const forward = async (args: string[], flags: Flags) => {
   const { page, close } = await connect(flags.tab)
   await page.goForward({ waitUntil: "domcontentloaded", timeout: flags.timeout })
   console.log(page.url())
-  close()
+  await close()
 }
diff --git a/src/commands/go.ts b/src/commands/go.ts
index 3546b2c..efb95b9 100644
--- a/src/commands/go.ts
+++ b/src/commands/go.ts
@@ -11,5 +11,5 @@ export const go = async (args: string[], flags: Flags) => {
   const { page, close } = await connect(flags.tab)
   await page.goto(url, { waitUntil: "domcontentloaded", timeout: flags.timeout })
   console.log(page.url())
-  close()
+  await close()
 }
diff --git a/src/commands/js.ts b/src/commands/js.ts
index e462f62..9a417da 100644
--- a/src/commands/js.ts
+++ b/src/commands/js.ts
@@ -14,7 +14,7 @@ export const js = async (args: string[], flags: Flags) => {
 
   const { page, close } = await connect(flags.tab)
   const result = await page.evaluate(code)
-  close()
+  await close()
 
   if (result === undefined || result === null) return
   console.log(typeof result === "string" ? result : JSON.stringify(result, null, 2))
diff --git a/src/commands/key.ts b/src/commands/key.ts
index ff7ee3f..5e31d62 100644
--- a/src/commands/key.ts
+++ b/src/commands/key.ts
@@ -25,5 +25,5 @@ export const key = async (args: string[], flags: Flags) => {
     for (const m of [...modifiers].reverse()) await page.keyboard.up(m as KeyInput)
   }
 
-  close()
+  await close()
 }
diff --git a/src/commands/move.ts b/src/commands/move.ts
index a64d088..c0cd175 100644
--- a/src/commands/move.ts
+++ b/src/commands/move.ts
@@ -16,5 +16,5 @@ export const move = async (args: string[], flags: Flags) => {
 
   const { page, close } = await connect(flags.tab)
   await page.mouse.move(x, y)
-  close()
+  await close()
 }
diff --git a/src/commands/scroll.ts b/src/commands/scroll.ts
index 055da1e..82b1886 100644
--- a/src/commands/scroll.ts
+++ b/src/commands/scroll.ts
@@ -24,5 +24,5 @@ export const scroll = async (args: string[], flags: Flags) => {
 
   const { page, close } = await connect(flags.tab)
   await page.evaluate(({ x, y }) => window.scrollBy(x, y), { x: delta.x * px, y: delta.y * px })
-  close()
+  await close()
 }
diff --git a/src/commands/shot.ts b/src/commands/shot.ts
index 1e1f42d..e8387ea 100644
--- a/src/commands/shot.ts
+++ b/src/commands/shot.ts
@@ -6,5 +6,5 @@ export const shot = async (args: string[], flags: Flags) => {
   const { page, close } = await connect(flags.tab)
   await page.screenshot({ path, type: "png" })
   console.log(path)
-  close()
+  await close()
 }
diff --git a/src/commands/snap.ts b/src/commands/snap.ts
index 49b5fec..e9c4196 100644
--- a/src/commands/snap.ts
+++ b/src/commands/snap.ts
@@ -1,5 +1,4 @@
 import { connect } from "../lib/browser"
-import { VIEWPORT } from "../lib/config"
 import type { Flags } from "../lib/flags"
 
 // Chrome's AX tree for names/roles + DOM.getBoxModel for coordinates.
@@ -25,6 +24,11 @@ interface SnapElement {
   state: Record<string, unknown>
 }
 
+interface Viewport {
+  width: number
+  height: number
+}
+
 const getBox = async (client: any, backendNodeId: number) => {
   const { model } = await client.send("DOM.getBoxModel", { backendNodeId }) as { model: any }
   if (model.width === 0 || model.height === 0) return null
@@ -35,8 +39,8 @@ const getBox = async (client: any, backendNodeId: number) => {
   }
 }
 
-const inViewport = ({ x, y }: { x: number; y: number }) =>
-  x >= 0 && x <= VIEWPORT.width && y >= 0 && y <= VIEWPORT.height + VIEWPORT_MARGIN
+const inViewport = ({ x, y }: { x: number; y: number }, viewport: Viewport) =>
+  x >= 0 && x <= viewport.width && y >= 0 && y <= viewport.height + VIEWPORT_MARGIN
 
 const extractState = (properties: any[]) =>
   (properties ?? []).reduce<Record<string, unknown>>((acc, p) => {
@@ -65,6 +69,11 @@ export const snap = async (args: string[], flags: Flags) => {
   const { page, close } = await connect(flags.tab)
   const client = await page.createCDPSession()
 
+  const viewport = await page.evaluate(() => ({
+    width: window.innerWidth,
+    height: window.innerHeight,
+  }))
+
   const { nodes } = await client.send("Accessibility.getFullAXTree") as { nodes: any[] }
 
   const interesting = nodes.filter(n =>
@@ -75,7 +84,7 @@ export const snap = async (args: string[], flags: Flags) => {
     interesting.map(async (n): Promise<SnapElement | null> => {
       try {
         const box = await getBox(client, n.backendDOMNodeId)
-        if (!box || !inViewport(box)) return null
+        if (!box || !inViewport(box, viewport)) return null
 
         return {
           role: n.role.value,
@@ -92,7 +101,7 @@ export const snap = async (args: string[], flags: Flags) => {
     .sort((a, b) => a.y - b.y || a.x - b.x)
 
   await client.detach()
-  close()
+  await close()
 
   if (flags.json) {
     console.log(JSON.stringify(elements, null, 2))
diff --git a/src/commands/tab.ts b/src/commands/tab.ts
new file mode 100644
index 0000000..9d9850b
--- /dev/null
+++ b/src/commands/tab.ts
@@ -0,0 +1,91 @@
+import puppeteer from "puppeteer-core"
+import { CDP_URL, VIEWPORT } from "../lib/config"
+import type { Flags } from "../lib/flags"
+
+const subcommands = { list, new: newTab, close }
+
+const help = `Usage: mb tab <list|new|close> [args]
+
+  list              List open tabs
+  new [url]         Open new tab, print index
+  close [n]         Close tab (default: last)`
+
+export const tab = async (args: string[], flags: Flags) => {
+  const [sub, ...rest] = args
+
+  if (!sub || !(sub in subcommands)) {
+    console.error(help)
+    process.exit(1)
+  }
+
+  const handler = subcommands[sub as keyof typeof subcommands]
+  await handler(rest, flags)
+}
+
+async function list(_args: string[], flags: Flags) {
+  const browser = await puppeteer.connect({ browserURL: CDP_URL, defaultViewport: VIEWPORT })
+  const pages = await browser.pages()
+
+  const entries = await Promise.all(
+    pages.map(async (page, i) => ({
+      index: i,
+      url: page.url(),
+      title: await page.title(),
+    }))
+  )
+
+  await browser.disconnect()
+
+  if (flags.json) {
+    console.log(JSON.stringify(entries, null, 2))
+    return
+  }
+
+  for (const { index, url, title } of entries) {
+    console.log(`${index}\t${url}\t${title}`)
+  }
+}
+
+async function newTab(args: string[], flags: Flags) {
+  const url = args[0]
+  const browser = await puppeteer.connect({ browserURL: CDP_URL, defaultViewport: VIEWPORT })
+  const page = await browser.newPage()
+
+  if (url) {
+    try {
+      await page.goto(url, { waitUntil: "domcontentloaded", timeout: flags.timeout })
+    } catch (e) {
+      await page.close()
+      await browser.disconnect()
+      throw e
+    }
+  }
+
+  const pages = await browser.pages()
+  const index = pages.indexOf(page)
+  await browser.disconnect()
+  console.log(index)
+}
+
+async function close(args: string[], _flags: Flags) {
+  const browser = await puppeteer.connect({ browserURL: CDP_URL, defaultViewport: VIEWPORT })
+  const pages = await browser.pages()
+
+  if (pages.length <= 1) {
+    await browser.disconnect()
+    throw new Error("Cannot close the last tab")
+  }
+
+  const index = args[0] !== undefined ? Number(args[0]) : pages.length - 1
+
+  if (!Number.isInteger(index) || index < 0 || index >= pages.length) {
+    await browser.disconnect()
+    throw new Error(`Invalid tab index: ${args[0]}. Open tabs: 0-${pages.length - 1}`)
+  }
+
+  const target = pages[index]!
+  const url = target.url()
+  await target.close()
+  await browser.disconnect()
+  console.log(`Closed tab ${index}\t${url}`)
+}
diff --git a/src/commands/text.ts b/src/commands/text.ts
index a449ea7..30d5b67 100644
--- a/src/commands/text.ts
+++ b/src/commands/text.ts
@@ -10,7 +10,7 @@ export const text = async (args: string[], flags: Flags) => {
     return el?.innerText?.trim() ?? null
   }, selector)
 
-  close()
+  await close()
 
   if (content === null) {
     console.error(`Selector not found: ${selector}`)
diff --git a/src/commands/type.ts b/src/commands/type.ts
index 19ad68c..98318a5 100644
--- a/src/commands/type.ts
+++ b/src/commands/type.ts
@@ -30,5 +30,5 @@ export const type = async (args: string[], flags: Flags) => {
   // Type replaces selection (or appends if nothing selected)
   await page.keyboard.type(text)
 
-  close()
+  await close()
 }
diff --git a/src/commands/url.ts b/src/commands/url.ts
index cae5637..2d4852a 100644
--- a/src/commands/url.ts
+++ b/src/commands/url.ts
@@ -4,5 +4,5 @@ import type { Flags } from "../lib/flags"
 export const url = async (args: string[], flags: Flags) => {
   const { page, close } = await connect(flags.tab)
   console.log(page.url())
-  close()
+  await close()
 }
diff --git a/src/commands/wait.ts b/src/commands/wait.ts
index 466cf4a..9f4b9be 100644
--- a/src/commands/wait.ts
+++ b/src/commands/wait.ts
@@ -13,13 +13,13 @@ export const wait = async (args: string[], flags: Flags) => {
   const ms = +target
   if (!isNaN(ms) && target === String(ms)) {
     await new Promise(r => setTimeout(r, ms))
-    close()
+    await close()
     return
   }
 
   if (target === "networkidle") {
     await page.waitForNetworkIdle({ timeout: flags.timeout })
-    close()
+    await close()
     return
   }
 
@@ -29,10 +29,10 @@ export const wait = async (args: string[], flags: Flags) => {
       { timeout: flags.timeout },
       target.slice(4)
     )
-    close()
+    await close()
     return
   }
 
   await page.waitForSelector(target, { timeout: flags.timeout })
-  close()
+  await close()
 }
diff --git a/src/index.ts b/src/index.ts
index 646fa47..fc73e17 100755
--- a/src/index.ts
+++ b/src/index.ts
@@ -16,8 +16,9 @@ import { scroll } from "./commands/scroll"
 import { js } from "./commands/js"
 import { wait } from "./commands/wait"
 import { audit } from "./commands/audit"
+import { tab } from "./commands/tab"
 
-const commands = { go, url, back, forward, shot, snap, text, click, type, fill, key, move, drag, scroll, js, wait, audit }
+const commands = { go, url, back, forward, shot, snap, text, click, type, fill, key, move, drag, scroll, js, wait, audit, tab }
 
 const help = `mb — Browser CLI for Agents
 
@@ -48,6 +49,11 @@ Other:
   wait <target>         Wait for ms/selector/networkidle/url:...
   audit                 Design audit (colors, fonts, spacing, contrast)
 
+Tabs:
+  tab list              List open tabs
+  tab new [url]         Open new tab, print index
+  tab close [n]         Close tab (default: last)
+
 Flags:
   --timeout <ms>        Timeout (default: 30000)
   --tab <n>             Tab index (default: 0)
diff --git a/src/lib/browser.ts b/src/lib/browser.ts
index 4fc0204..7eaa179 100644
--- a/src/lib/browser.ts
+++ b/src/lib/browser.ts
@@ -4,12 +4,16 @@ import { CDP_URL, VIEWPORT } from "./config"
 export const connect = async (tab = 0) => {
   const browser = await puppeteer.connect({
     browserURL: CDP_URL,
+    defaultViewport: VIEWPORT,
   })
   const pages = await browser.pages()
-  const page = pages[tab] ?? pages[0]
+  if (tab < 0 || tab >= pages.length) {
+    await browser.disconnect()
+    throw new Error(`Invalid tab index: ${tab}. Open tabs: 0-${pages.length - 1}`)
+  }
+  const page = pages[tab]!
   if (!page) throw new Error("No pages found")
-  await page.setViewport(VIEWPORT)
-  return { browser, page, close: () => browser.disconnect() }
+  return { browser, page, close: () => browser.disconnect() as Promise<void> }
 }
 
 interface WithPageInput {
@@ -24,6 +28,6 @@ export const withPage = async <T>(
   try {
     return await fn(page)
   } finally {
-    close()
+    await close()
   }
 }