diff --git a/.changeset/thirty-news-smell.md b/.changeset/thirty-news-smell.md
new file mode 100644
index 00000000000..ee227adc9f7
--- /dev/null
+++ b/.changeset/thirty-news-smell.md
@@ -0,0 +1,5 @@
+---
+'@shopify/theme': patch
+---
+
+Fix Cart rate limiting issue
diff --git a/packages/theme/src/cli/utilities/theme-environment/proxy.test.ts b/packages/theme/src/cli/utilities/theme-environment/proxy.test.ts
index 38434b60856..36693898e52 100644
--- a/packages/theme/src/cli/utilities/theme-environment/proxy.test.ts
+++ b/packages/theme/src/cli/utilities/theme-environment/proxy.test.ts
@@ -5,7 +5,7 @@ import {
   patchRenderingResponse,
   proxyStorefrontRequest,
 } from './proxy.js'
-import {describe, test, expect, vi, afterEach} from 'vitest'
+import {describe, test, expect} from 'vitest'
 import {createEvent} from 'h3'
 import {IncomingMessage, ServerResponse} from 'node:http'
 
@@ -403,116 +403,5 @@ describe('dev proxy', () => {
         'Request failed: Hostname mismatch. Expected host: cdn.shopify.com. Resulting URL hostname: evil.com',
       )
     })
-
-    const themeCtx = {
-      session: {
-        storeFqdn: 'my-store.myshopify.com',
-        storefrontToken: 'test-sfr-token',
-        storefrontPassword: '',
-        sessionCookies: {},
-      },
-      options: {host: 'localhost', port: '9292'},
-      localThemeFileSystem: {files: new Map()},
-      localThemeExtensionFileSystem: {files: new Map()},
-      type: 'theme',
-    } as unknown as DevServerContext
-
-    const extensionCtx = {
-      ...themeCtx,
-      type: 'theme-extension',
-    } as unknown as DevServerContext
-
-    let fetchMock: ReturnType<typeof vi.fn>
-
-    afterEach(() => {
-      vi.unstubAllGlobals()
-    })
-
-    function stubFetchAndProxy(method: string, path: string, context: DevServerContext) {
-      fetchMock = vi.fn().mockResolvedValue(new Response('ok'))
-      vi.stubGlobal('fetch', fetchMock)
-      const event = createH3Event(method, path)
-      return proxyStorefrontRequest(event, context)
-    }
-
-    function getAuthHeader(): string | undefined {
-      const headers = fetchMock.mock.calls[0]![1].headers as {[key: string]: string}
-      return headers.Authorization ?? headers.authorization
-    }
-
-    test('excludes Bearer token for POST /cart/add.js', async () => {
-      await stubFetchAndProxy('POST', '/cart/add.js', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for POST /cart/update.js', async () => {
-      await stubFetchAndProxy('POST', '/cart/update.js', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for GET /cart.js', async () => {
-      await stubFetchAndProxy('GET', '/cart.js', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for GET /cart.json', async () => {
-      await stubFetchAndProxy('GET', '/cart.json', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for POST /cart (bare)', async () => {
-      await stubFetchAndProxy('POST', '/cart', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for POST /cart/change.js', async () => {
-      await stubFetchAndProxy('POST', '/cart/change.js', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for GET /checkouts/abc123', async () => {
-      await stubFetchAndProxy('GET', '/checkouts/abc123', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for GET /account/logout', async () => {
-      await stubFetchAndProxy('GET', '/account/logout', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for GET /cart.js?sections=header (query string)', async () => {
-      await stubFetchAndProxy('GET', '/cart.js?sections=header', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for POST /cart/add.js?sections=main-cart-items (query string)', async () => {
-      await stubFetchAndProxy('POST', '/cart/add.js?sections=main-cart-items', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('excludes Bearer token for GET /account?foo=bar (query string with $ anchor)', async () => {
-      await stubFetchAndProxy('GET', '/account?foo=bar', themeCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
-
-    test('includes Bearer token for GET /cdn/shop/t/10/assets/theme.css', async () => {
-      await stubFetchAndProxy('GET', '/cdn/shop/t/10/assets/theme.css', themeCtx)
-      expect(getAuthHeader()).toBe('Bearer test-sfr-token')
-    })
-
-    test('includes Bearer token for GET /some-path.js', async () => {
-      await stubFetchAndProxy('GET', '/some-path.js', themeCtx)
-      expect(getAuthHeader()).toBe('Bearer test-sfr-token')
-    })
-
-    test('includes Bearer token for GET /checkouts/internal/something (negative lookahead)', async () => {
-      await stubFetchAndProxy('GET', '/checkouts/internal/something', themeCtx)
-      expect(getAuthHeader()).toBe('Bearer test-sfr-token')
-    })
-
-    test('excludes Bearer token for theme-extension context', async () => {
-      await stubFetchAndProxy('GET', '/cdn/shop/t/10/assets/theme.css', extensionCtx)
-      expect(getAuthHeader()).toBeUndefined()
-    })
   })
 })
diff --git a/packages/theme/src/cli/utilities/theme-environment/proxy.ts b/packages/theme/src/cli/utilities/theme-environment/proxy.ts
index 57ab7a60354..debfc8e6d94 100644
--- a/packages/theme/src/cli/utilities/theme-environment/proxy.ts
+++ b/packages/theme/src/cli/utilities/theme-environment/proxy.ts
@@ -16,9 +16,6 @@ export const EXTENSION_CDN_PREFIX = '/ext/cdn/'
 
 const API_COLLECT_PATH = '/api/collect'
 const CART_PATTERN = /^\/cart\//
-// Broader than CART_PATTERN (routing) -- covers /cart, /cart.js, /cart.json for auth exclusion.
-// CART_PATTERN only matches /cart/... subpaths to avoid proxying GET /cart (the cart HTML page).
-const CART_SESSION_PATTERN = /^\/cart(\/|\.js|\.json|$)/
 const CHECKOUT_PATTERN = /^\/checkouts\/(?!internal\/)/
 const ACCOUNT_PATTERN = /^\/account(\/login\/multipass(\/[^/]+)?|\/logout)?\/?$/
 const VANITY_CDN_PATTERN = new RegExp(`^${VANITY_CDN_PREFIX}`)
@@ -117,18 +114,6 @@ export function canProxyRequest(event: H3Event) {
   return Boolean(extension) || acceptsType !== '*/*'
 }
 
-// Cart, checkout, and account endpoints use session-cookie auth, not Bearer tokens.
-// CHECKOUT_PATTERN and ACCOUNT_PATTERN are reused from routing because their
-// routing and auth scopes currently align; changes to those patterns should
-// consider the auth implications here.
-function needsBearerToken(path: string): boolean {
-  const [pathname] = path.split('?') as [string]
-  if (CART_SESSION_PATTERN.test(pathname)) return false
-  if (CHECKOUT_PATTERN.test(pathname)) return false
-  if (ACCOUNT_PATTERN.test(pathname)) return false
-  return true
-}
-
 function getStoreFqdnForRegEx(ctx: DevServerContext) {
   return ctx.session.storeFqdn.replace(/\\/g, '\\\\').replace(/\./g, '\\.')
 }
@@ -341,9 +326,8 @@ export function proxyStorefrontRequest(event: H3Event, ctx: DevServerContext): P
     Cookie: buildCookies(ctx.session, {headers}),
   }
 
-  // Cart, checkout, and account endpoints use cookie-based auth.
-  // Sending a Bearer token causes SFR to select token auth, which lacks cart scopes.
-  if (ctx.type === 'theme' && needsBearerToken(event.path)) {
+  // Only include Authorization for theme dev, not theme-extensions
+  if (ctx.type === 'theme') {
     baseHeaders.Authorization = `Bearer ${ctx.session.storefrontToken}`
   }