diff --git a/apps/web-wasm/src/App.vue b/apps/web-wasm/src/App.vue
index 7a0e71da..454bf63a 100644
--- a/apps/web-wasm/src/App.vue
+++ b/apps/web-wasm/src/App.vue
@@ -14,7 +14,7 @@ import { reportError } from '@/services/log-report'
 import { useLayoutStore } from '@/stores/layout'
 import { useSessionStore } from '@/stores/session'
 import { useSettingsStore } from '@/stores/settings'
-import { StartupLoading } from '@/components/UI'
+import { StartupLoading, UiButton, UiIcon } from '@/components/UI'
 import { PLATFORM_CAPABILITIES } from '@/utils/platform-capabilities'
 import WebSettingsModal from './components/settings/WebSettingsModal.vue'
 
@@ -91,12 +91,12 @@ onMounted(() => {
       <template v-if="!isInitialized">
         <div class="flex h-full w-full items-center justify-center">
           <div v-if="initError" class="flex flex-col items-center justify-center gap-3 px-6 text-center">
-            <UIcon name="i-heroicons-exclamation-triangle" class="h-8 w-8 text-red-500" />
+            <UiIcon name="i-heroicons-exclamation-triangle" class="h-8 w-8 text-red-500" />
             <p class="text-sm text-gray-700 dark:text-gray-300">{{ t('common.initFailed') }}</p>
             <p class="max-w-sm text-xs text-gray-500">{{ initError }}</p>
-            <UButton size="sm" color="primary" variant="soft" @click="initializeApp">
+            <UiButton size="sm" variant="soft" @click="initializeApp">
               {{ t('common.retry') }}
-            </UButton>
+            </UiButton>
           </div>
           <StartupLoading v-else />
         </div>
diff --git a/src/App.vue b/src/App.vue
index 772ac26f..2bd53015 100644
--- a/src/App.vue
+++ b/src/App.vue
@@ -5,7 +5,7 @@ import { useRoute, useRouter } from 'vue-router'
 import { useI18n } from 'vue-i18n'
 import TitleBar from '@/components/common/TitleBar.vue'
 import Sidebar from '@/components/common/Sidebar.vue'
-import { StartupLoading } from '@/components/UI'
+import { StartupLoading, UiButton, UiIcon } from '@/components/UI'
 import { useSessionStore } from '@/stores/session'
 import { useLayoutStore } from '@/stores/layout'
 import { useSettingsStore } from '@/stores/settings'
@@ -421,12 +421,12 @@ onUnmounted(() => {
               v-if="startupPresentation.showError"
               class="flex flex-col items-center justify-center gap-3 text-center"
             >
-              <UIcon name="i-heroicons-exclamation-triangle" class="h-8 w-8 text-red-500" />
+              <UiIcon name="i-heroicons-exclamation-triangle" class="h-8 w-8 text-red-500" />
               <p class="text-sm text-gray-700 dark:text-gray-300">{{ t('common.initFailed') }}</p>
               <p class="max-w-sm text-xs text-gray-500">{{ initError }}</p>
-              <UButton size="sm" color="primary" variant="soft" @click="initializeApp">
+              <UiButton size="sm" variant="soft" @click="initializeApp">
                 {{ t('common.retry') }}
-              </UButton>
+              </UiButton>
             </div>
             <StartupLoading
               v-else
diff --git a/src/components/UI/LoadingState.vue b/src/components/UI/LoadingState.vue
index aa5d1374..ccc6a7f0 100644
--- a/src/components/UI/LoadingState.vue
+++ b/src/components/UI/LoadingState.vue
@@ -7,6 +7,7 @@
 import { computed, ref } from 'vue'
 import { useInsightViewLoading } from './insight-view-loading'
 import LoadingDots from './LoadingDots.vue'
+import UiIcon from './primitives/UiIcon.vue'
 
 const props = withDefaults(
   defineProps<{
@@ -47,7 +48,7 @@ const usePageIndicator = computed(() => props.variant === 'page' || props.varian
   <div v-if="!isCoordinatedPageLoading" :class="containerClass" role="status" aria-live="polite">
     <div class="flex flex-col items-center justify-center text-center">
       <LoadingDots v-if="usePageIndicator" />
-      <UIcon v-else name="i-heroicons-arrow-path" class="h-6 w-6 animate-spin text-pink-500" />
+      <UiIcon v-else name="i-heroicons-arrow-path" size="xl" class="animate-spin text-pink-500" />
       <p v-if="text" class="mt-2 text-sm text-gray-500">{{ text }}</p>
     </div>
   </div>
diff --git a/src/components/UI/StatCard.vue b/src/components/UI/StatCard.vue
index 4dc0168e..858bd552 100644
--- a/src/components/UI/StatCard.vue
+++ b/src/components/UI/StatCard.vue
@@ -4,6 +4,7 @@
  * 基于 ThemeCard 的组合封装，用于展示单个统计指标
  */
 import ThemeCard from './ThemeCard.vue'
+import UiIcon from './primitives/UiIcon.vue'
 
 defineProps<{
   /** 指标标签 */
@@ -56,7 +57,7 @@ const iconBgMap: Record<string, string> = {
         class="ml-4 flex h-10 w-10 shrink-0 items-center justify-center rounded-xl"
         :class="iconBgMap[iconBg || 'gray']"
       >
-        <UIcon v-if="icon.startsWith('i-')" :name="icon" class="h-5 w-5" />
+        <UiIcon v-if="icon.startsWith('i-')" :name="icon" size="lg" />
         <span v-else class="text-xl">{{ icon }}</span>
       </div>
     </div>
diff --git a/src/components/UI/index.ts b/src/components/UI/index.ts
index 95f9a63f..b800d896 100644
--- a/src/components/UI/index.ts
+++ b/src/components/UI/index.ts
@@ -19,3 +19,4 @@ export { default as FileDropZone } from './FileDropZone.vue'
 export { default as DatePicker } from './DatePicker.vue'
 export { default as TopNSelect } from './TopNSelect.vue'
 export { default as ScrollableChart } from './ScrollableChart.vue'
+export * from './primitives'
diff --git a/src/components/UI/primitives/UiBadge.vue b/src/components/UI/primitives/UiBadge.vue
new file mode 100644
index 00000000..5890cd86
--- /dev/null
+++ b/src/components/UI/primitives/UiBadge.vue
@@ -0,0 +1,52 @@
+<script setup lang="ts">
+import { computed } from 'vue'
+import { toNuxtUiColor } from './nuxt-ui-adapter'
+import { usePrimitiveAttrs } from './primitive-contracts'
+import type { UiBadgeVariant, UiSize, UiTone } from './types'
+
+defineOptions({ inheritAttrs: false })
+
+const props = withDefaults(
+  defineProps<{
+    tone?: UiTone
+    variant?: UiBadgeVariant
+    size?: UiSize
+    label?: string | number
+    icon?: string
+    trailingIcon?: string
+  }>(),
+  {
+    tone: 'neutral',
+    variant: 'soft',
+    size: 'md',
+    label: undefined,
+    icon: undefined,
+    trailingIcon: undefined,
+  }
+)
+
+const color = computed(() => toNuxtUiColor(props.tone))
+const primitiveAttrs = usePrimitiveAttrs()
+</script>
+
+<template>
+  <UBadge
+    v-bind="primitiveAttrs"
+    :color="color"
+    :variant="variant"
+    :size="size"
+    :label="label"
+    :icon="icon"
+    :trailing-icon="trailingIcon"
+  >
+    <template v-if="$slots.leading" #leading>
+      <slot name="leading" />
+    </template>
+    <template v-if="$slots.default" #default>
+      <slot />
+    </template>
+    <template v-if="$slots.trailing" #trailing>
+      <slot name="trailing" />
+    </template>
+  </UBadge>
+</template>
diff --git a/src/components/UI/primitives/UiButton.ssr.test.ts b/src/components/UI/primitives/UiButton.ssr.test.ts
new file mode 100644
index 00000000..6064fe98
--- /dev/null
+++ b/src/components/UI/primitives/UiButton.ssr.test.ts
@@ -0,0 +1,90 @@
+import assert from 'node:assert/strict'
+import { after, before, describe, it } from 'node:test'
+import { renderToString } from '@vue/server-renderer'
+import vue from '@vitejs/plugin-vue'
+import { createSSRApp, defineComponent, h, type Component } from 'vue'
+import { createServer, type ViteDevServer } from 'vite'
+
+let server: ViteDevServer
+let UiButton: Component
+
+const UButtonStub = defineComponent({
+  inheritAttrs: false,
+  props: {
+    label: String,
+    loading: Boolean,
+    disabled: Boolean,
+  },
+  setup(props, { attrs, slots }) {
+    return () =>
+      h(
+        'button',
+        {
+          ...attrs,
+          disabled: props.disabled,
+          'data-loading': props.loading ? 'true' : undefined,
+        },
+        slots.default?.() ?? props.label
+      )
+  },
+})
+
+before(async () => {
+  server = await createServer({
+    configFile: false,
+    appType: 'custom',
+    server: { middlewareMode: true },
+    optimizeDeps: { noDiscovery: true },
+    plugins: [vue()],
+  })
+  UiButton = (await server.ssrLoadModule('/src/components/UI/primitives/UiButton.vue')).default as Component
+})
+
+after(async () => {
+  await server.close()
+})
+
+async function renderButton(props: Record<string, unknown>, text?: string): Promise<string> {
+  const app = createSSRApp({
+    render: () => h(UiButton, props, text === undefined ? undefined : { default: () => text }),
+  })
+  app.component('UButton', UButtonStub)
+  return renderToString(app)
+}
+
+describe('UiButton rendered contract', () => {
+  it('renders its explicit accessible label and strips vendor escape hatches', async () => {
+    const html = await renderButton({
+      icon: 'i-heroicons-x-mark',
+      accessibleLabel: 'Close',
+      ui: { base: 'vendor-override' },
+      portal: false,
+    })
+
+    assert.match(html, /aria-label="Close"/)
+    assert.doesNotMatch(html, /vendor-override|portal=/)
+  })
+
+  it('rejects icon-only buttons without an explicit accessible label', async () => {
+    await assert.rejects(() => renderButton({ icon: 'i-heroicons-x-mark' }), /visible text or an accessible label/)
+    await assert.rejects(
+      () => renderButton({ icon: 'i-heroicons-x-mark', 'aria-label': 'Bypassed label' }),
+      /visible text or an accessible label/
+    )
+  })
+
+  it('renders visible slot text as the button name', async () => {
+    const html = await renderButton({}, 'Retry')
+    assert.match(html, /Retry/)
+  })
+
+  it('keeps disabled and loading buttons non-interactive', async () => {
+    const disabledHtml = await renderButton({ label: 'Disabled', disabled: true })
+    const loadingHtml = await renderButton({ label: 'Loading', loading: true })
+
+    assert.match(disabledHtml, /disabled/)
+    assert.match(loadingHtml, /disabled/)
+    assert.match(loadingHtml, /aria-busy="true"/)
+    assert.match(loadingHtml, /data-loading="true"/)
+  })
+})
diff --git a/src/components/UI/primitives/UiButton.vue b/src/components/UI/primitives/UiButton.vue
new file mode 100644
index 00000000..b2276c69
--- /dev/null
+++ b/src/components/UI/primitives/UiButton.vue
@@ -0,0 +1,91 @@
+<script setup lang="ts">
+import { computed, useSlots } from 'vue'
+import { toNuxtUiColor } from './nuxt-ui-adapter'
+import { assertButtonAccessibleName, usePrimitiveAttrs } from './primitive-contracts'
+import type { UiButtonVariant, UiSize, UiTone } from './types'
+
+defineOptions({ inheritAttrs: false })
+
+const props = withDefaults(
+  defineProps<{
+    tone?: UiTone
+    variant?: UiButtonVariant
+    size?: UiSize
+    type?: 'button' | 'submit' | 'reset'
+    label?: string
+    accessibleLabel?: string
+    icon?: string
+    trailingIcon?: string
+    loading?: boolean
+    disabled?: boolean
+    block?: boolean
+  }>(),
+  {
+    tone: 'primary',
+    variant: 'solid',
+    size: 'md',
+    type: 'button',
+    label: undefined,
+    accessibleLabel: undefined,
+    icon: undefined,
+    trailingIcon: undefined,
+    loading: false,
+    disabled: false,
+    block: false,
+  }
+)
+
+const emit = defineEmits<{
+  click: [event: MouseEvent]
+  focus: [event: FocusEvent]
+  blur: [event: FocusEvent]
+  keydown: [event: KeyboardEvent]
+  keyup: [event: KeyboardEvent]
+}>()
+
+const slots = useSlots()
+const primitiveAttrs = usePrimitiveAttrs(['aria-label', 'aria-busy'])
+const color = computed(() => toNuxtUiColor(props.tone))
+const resolvedAccessibleLabel = computed(() => {
+  assertButtonAccessibleName({
+    label: props.label,
+    accessibleLabel: props.accessibleLabel,
+    hasDefaultSlot: Boolean(slots.default),
+  })
+  return props.accessibleLabel
+})
+const isDisabled = computed(() => props.disabled || props.loading)
+</script>
+
+<template>
+  <UButton
+    v-bind="primitiveAttrs"
+    :type="type"
+    :label="label"
+    :aria-label="resolvedAccessibleLabel"
+    :aria-busy="loading ? 'true' : undefined"
+    :icon="icon"
+    :trailing-icon="trailingIcon"
+    :color="color"
+    :variant="variant"
+    :size="size"
+    :loading="loading"
+    :disabled="isDisabled"
+    :block="block"
+    @click="emit('click', $event)"
+    @focus="emit('focus', $event)"
+    @blur="emit('blur', $event)"
+    @keydown="emit('keydown', $event)"
+    @keyup="emit('keyup', $event)"
+  >
+    <template v-if="$slots.leading" #leading>
+      <slot name="leading" />
+    </template>
+    <template v-if="$slots.default" #default>
+      <slot />
+    </template>
+    <template v-if="$slots.trailing" #trailing>
+      <slot name="trailing" />
+    </template>
+  </UButton>
+</template>
diff --git a/src/components/UI/primitives/UiIcon.vue b/src/components/UI/primitives/UiIcon.vue
new file mode 100644
index 00000000..a3a54895
--- /dev/null
+++ b/src/components/UI/primitives/UiIcon.vue
@@ -0,0 +1,36 @@
+<script setup lang="ts">
+import { computed } from 'vue'
+import { usePrimitiveAttrs } from './primitive-contracts'
+import type { UiSize } from './types'
+
+defineOptions({ inheritAttrs: false })
+
+const props = defineProps<{
+  name: string
+  size?: UiSize
+  label?: string
+}>()
+
+const sizeClass = computed(() => {
+  if (!props.size) return undefined
+  return {
+    xs: 'h-3 w-3',
+    sm: 'h-3.5 w-3.5',
+    md: 'h-4 w-4',
+    lg: 'h-5 w-5',
+    xl: 'h-6 w-6',
+  }[props.size]
+})
+const primitiveAttrs = usePrimitiveAttrs(['aria-label', 'aria-hidden', 'role'])
+</script>
+
+<template>
+  <UIcon
+    v-bind="primitiveAttrs"
+    :name="name"
+    :class="sizeClass"
+    :role="label ? 'img' : undefined"
+    :aria-label="label"
+    :aria-hidden="label ? undefined : 'true'"
+  />
+</template>
diff --git a/src/components/UI/primitives/UiIconButton.vue b/src/components/UI/primitives/UiIconButton.vue
new file mode 100644
index 00000000..58725fbe
--- /dev/null
+++ b/src/components/UI/primitives/UiIconButton.vue
@@ -0,0 +1,54 @@
+<script setup lang="ts">
+import UiButton from './UiButton.vue'
+import { usePrimitiveAttrs } from './primitive-contracts'
+import type { UiButtonVariant, UiSize, UiTone } from './types'
+
+defineOptions({ inheritAttrs: false })
+
+withDefaults(
+  defineProps<{
+    icon: string
+    label: string
+    tone?: UiTone
+    variant?: UiButtonVariant
+    size?: UiSize
+    loading?: boolean
+    disabled?: boolean
+  }>(),
+  {
+    tone: 'neutral',
+    variant: 'ghost',
+    size: 'sm',
+    loading: false,
+    disabled: false,
+  }
+)
+
+const emit = defineEmits<{
+  click: [event: MouseEvent]
+  focus: [event: FocusEvent]
+  blur: [event: FocusEvent]
+  keydown: [event: KeyboardEvent]
+  keyup: [event: KeyboardEvent]
+}>()
+
+const primitiveAttrs = usePrimitiveAttrs()
+</script>
+
+<template>
+  <UiButton
+    v-bind="primitiveAttrs"
+    :icon="icon"
+    :accessible-label="label"
+    :tone="tone"
+    :variant="variant"
+    :size="size"
+    :loading="loading"
+    :disabled="disabled"
+    @click="emit('click', $event)"
+    @focus="emit('focus', $event)"
+    @blur="emit('blur', $event)"
+    @keydown="emit('keydown', $event)"
+    @keyup="emit('keyup', $event)"
+  />
+</template>
diff --git a/src/components/UI/primitives/UiProgress.vue b/src/components/UI/primitives/UiProgress.vue
new file mode 100644
index 00000000..72467274
--- /dev/null
+++ b/src/components/UI/primitives/UiProgress.vue
@@ -0,0 +1,97 @@
+<script setup lang="ts">
+import { computed } from 'vue'
+import { assertProgressLabel, getUiProgressState, usePrimitiveAttrs } from './primitive-contracts'
+import type { UiSize, UiTone } from './types'
+
+defineOptions({ inheritAttrs: false })
+
+const props = withDefaults(
+  defineProps<{
+    label: string
+    value?: number | null
+    max?: number
+    tone?: UiTone
+    size?: UiSize
+    showValue?: boolean
+    inverted?: boolean
+    statusText?: string
+  }>(),
+  {
+    value: null,
+    max: 100,
+    tone: 'primary',
+    size: 'md',
+    showValue: false,
+    inverted: false,
+    statusText: undefined,
+  }
+)
+
+assertProgressLabel(props.label)
+
+const primitiveAttrs = usePrimitiveAttrs()
+const progressState = computed(() => getUiProgressState(props.value, props.max))
+const roundedPercentage = computed(() =>
+  progressState.value.percentage === null ? null : Math.round(progressState.value.percentage)
+)
+const valueText = computed(
+  () => props.statusText ?? (roundedPercentage.value === null ? undefined : `${roundedPercentage.value}%`)
+)
+const barStyle = computed(() =>
+  progressState.value.percentage === null ? undefined : { width: `${progressState.value.percentage}%` }
+)
+const sizeClass = computed(
+  () =>
+    ({
+      xs: 'h-1',
+      sm: 'h-1.5',
+      md: 'h-2',
+      lg: 'h-2.5',
+      xl: 'h-3',
+    })[props.size]
+)
+const toneClass = computed(
+  () =>
+    ({
+      primary: 'bg-primary-500',
+      neutral: 'bg-gray-500',
+      success: 'bg-green-500',
+      warning: 'bg-amber-500',
+      danger: 'bg-red-500',
+      info: 'bg-blue-500',
+    })[props.tone]
+)
+</script>
+
+<template>
+  <div v-bind="primitiveAttrs" class="w-full">
+    <div
+      v-if="showValue && roundedPercentage !== null"
+      class="mb-1 text-right text-xs text-gray-500 dark:text-gray-400"
+    >
+      <slot name="status" :value="progressState.value" :max="max" :percentage="roundedPercentage">
+        {{ roundedPercentage }}%
+      </slot>
+    </div>
+    <div
+      role="progressbar"
+      :aria-label="label"
+      :aria-valuemin="0"
+      :aria-valuemax="max"
+      :aria-valuenow="progressState.value ?? undefined"
+      :aria-valuetext="valueText"
+      :aria-busy="progressState.value === null ? 'true' : undefined"
+      class="flex w-full overflow-hidden rounded-full bg-gray-200 dark:bg-white/10"
+      :class="[sizeClass, inverted ? 'justify-end' : undefined]"
+    >
+      <div
+        class="h-full rounded-full transition-[width] duration-200 motion-reduce:transition-none"
+        :class="[
+          toneClass,
+          progressState.percentage === null ? 'w-1/2 animate-pulse motion-reduce:animate-none' : undefined,
+        ]"
+        :style="barStyle"
+      />
+    </div>
+  </div>
+</template>
diff --git a/src/components/UI/primitives/UiTooltip.vue b/src/components/UI/primitives/UiTooltip.vue
new file mode 100644
index 00000000..2623e7e3
--- /dev/null
+++ b/src/components/UI/primitives/UiTooltip.vue
@@ -0,0 +1,26 @@
+<script setup lang="ts">
+import type { UiTooltipPlacement } from './types'
+
+defineOptions({ inheritAttrs: false })
+
+withDefaults(
+  defineProps<{
+    text: string
+    placement?: UiTooltipPlacement
+    delay?: number
+    disabled?: boolean
+  }>(),
+  {
+    placement: 'bottom',
+    delay: 300,
+    disabled: false,
+  }
+)
+</script>
+
+<template>
+  <slot v-if="disabled || !text" />
+  <UTooltip v-else :text="text" :delay-duration="delay" :content="{ side: placement }">
+    <slot />
+  </UTooltip>
+</template>
diff --git a/src/components/UI/primitives/index.ts b/src/components/UI/primitives/index.ts
new file mode 100644
index 00000000..f5e75d9c
--- /dev/null
+++ b/src/components/UI/primitives/index.ts
@@ -0,0 +1,8 @@
+export { default as UiBadge } from './UiBadge.vue'
+export { default as UiButton } from './UiButton.vue'
+export { default as UiIcon } from './UiIcon.vue'
+export { default as UiIconButton } from './UiIconButton.vue'
+export { default as UiProgress } from './UiProgress.vue'
+export { default as UiTooltip } from './UiTooltip.vue'
+
+export type { UiBadgeVariant, UiButtonVariant, UiSize, UiTone, UiTooltipPlacement } from './types'
diff --git a/src/components/UI/primitives/nuxt-ui-adapter.ts b/src/components/UI/primitives/nuxt-ui-adapter.ts
new file mode 100644
index 00000000..f4c35944
--- /dev/null
+++ b/src/components/UI/primitives/nuxt-ui-adapter.ts
@@ -0,0 +1,16 @@
+import type { UiTone } from './types'
+
+type NuxtUiColor = 'primary' | 'neutral' | 'success' | 'warning' | 'error' | 'info'
+
+const NUXT_UI_COLOR_BY_TONE: Record<UiTone, NuxtUiColor> = {
+  primary: 'primary',
+  neutral: 'neutral',
+  success: 'success',
+  warning: 'warning',
+  danger: 'error',
+  info: 'info',
+}
+
+export function toNuxtUiColor(tone: UiTone): NuxtUiColor {
+  return NUXT_UI_COLOR_BY_TONE[tone]
+}
diff --git a/src/components/UI/primitives/primitive-contracts.test.ts b/src/components/UI/primitives/primitive-contracts.test.ts
new file mode 100644
index 00000000..4ae8e1dc
--- /dev/null
+++ b/src/components/UI/primitives/primitive-contracts.test.ts
@@ -0,0 +1,71 @@
+import assert from 'node:assert/strict'
+import { describe, it } from 'node:test'
+import { toNuxtUiColor } from './nuxt-ui-adapter'
+import {
+  assertButtonAccessibleName,
+  assertProgressLabel,
+  filterPrimitiveAttrs,
+  getUiProgressState,
+} from './primitive-contracts'
+import type { UiTone } from './types'
+
+describe('UI primitive contracts', () => {
+  it('maps semantic tones to the current Nuxt UI adapter', () => {
+    const cases: Array<[UiTone, ReturnType<typeof toNuxtUiColor>]> = [
+      ['primary', 'primary'],
+      ['neutral', 'neutral'],
+      ['success', 'success'],
+      ['warning', 'warning'],
+      ['danger', 'error'],
+      ['info', 'info'],
+    ]
+
+    for (const [tone, expected] of cases) {
+      assert.equal(toNuxtUiColor(tone), expected)
+    }
+  })
+
+  it('keeps stable DOM attributes without exposing vendor component props or listeners', () => {
+    const onClick = () => undefined
+    assert.deepEqual(
+      filterPrimitiveAttrs({
+        class: 'custom',
+        id: 'action',
+        'aria-label': 'Retry',
+        'data-test': 'retry',
+        ui: { base: 'vendor-override' },
+        portal: false,
+        onClick,
+      }),
+      {
+        class: 'custom',
+        id: 'action',
+        'aria-label': 'Retry',
+        'data-test': 'retry',
+      }
+    )
+  })
+
+  it('requires every button to have a visible or accessible name', () => {
+    assert.doesNotThrow(() => assertButtonAccessibleName({ label: 'Retry', hasDefaultSlot: false }))
+    assert.doesNotThrow(() => assertButtonAccessibleName({ accessibleLabel: 'Close', hasDefaultSlot: false }))
+    assert.doesNotThrow(() => assertButtonAccessibleName({ hasDefaultSlot: true }))
+    assert.throws(
+      () => assertButtonAccessibleName({ label: ' ', hasDefaultSlot: false }),
+      /visible text or an accessible label/
+    )
+  })
+
+  it('clamps determinate progress and preserves the indeterminate state', () => {
+    assert.deepEqual(getUiProgressState(null, 100), { value: null, percentage: null })
+    assert.deepEqual(getUiProgressState(-10, 100), { value: 0, percentage: 0 })
+    assert.deepEqual(getUiProgressState(25, 50), { value: 25, percentage: 50 })
+    assert.deepEqual(getUiProgressState(120, 100), { value: 100, percentage: 100 })
+    assert.throws(() => getUiProgressState(10, 0), /greater than zero/)
+  })
+
+  it('requires progress to expose a stable accessible name', () => {
+    assert.doesNotThrow(() => assertProgressLabel('Import progress'))
+    assert.throws(() => assertProgressLabel(' '), /non-empty accessible label/)
+  })
+})
diff --git a/src/components/UI/primitives/primitive-contracts.ts b/src/components/UI/primitives/primitive-contracts.ts
new file mode 100644
index 00000000..6eb53cb5
--- /dev/null
+++ b/src/components/UI/primitives/primitive-contracts.ts
@@ -0,0 +1,67 @@
+import { computed, useAttrs, type ComputedRef } from 'vue'
+
+const SAFE_PRIMITIVE_ATTRIBUTES = new Set(['class', 'style', 'id', 'title', 'tabindex'])
+
+export function filterPrimitiveAttrs(
+  attrs: Record<string, unknown>,
+  excludedAttributes: readonly string[] = []
+): Record<string, unknown> {
+  const excluded = new Set(excludedAttributes)
+  return Object.fromEntries(
+    Object.entries(attrs).filter(
+      ([name]) =>
+        !excluded.has(name) &&
+        (SAFE_PRIMITIVE_ATTRIBUTES.has(name) || name.startsWith('aria-') || name.startsWith('data-'))
+    )
+  )
+}
+
+export function usePrimitiveAttrs(excludedAttributes: readonly string[] = []): ComputedRef<Record<string, unknown>> {
+  const attrs = useAttrs()
+  return computed(() => filterPrimitiveAttrs(attrs, excludedAttributes))
+}
+
+interface ButtonAccessibleNameInput {
+  label?: string
+  accessibleLabel?: string
+  hasDefaultSlot: boolean
+}
+
+function hasText(value: unknown): value is string {
+  return typeof value === 'string' && value.trim().length > 0
+}
+
+export function assertButtonAccessibleName({
+  label,
+  accessibleLabel,
+  hasDefaultSlot,
+}: ButtonAccessibleNameInput): void {
+  if (hasText(label) || hasText(accessibleLabel) || hasDefaultSlot) return
+  throw new Error('UiButton requires visible text or an accessible label. Use UiIconButton for icon-only actions.')
+}
+
+export interface UiProgressState {
+  value: number | null
+  percentage: number | null
+}
+
+export function getUiProgressState(value: number | null, max: number): UiProgressState {
+  if (!Number.isFinite(max) || max <= 0) {
+    throw new RangeError('UiProgress max must be a finite number greater than zero.')
+  }
+  if (value === null) return { value: null, percentage: null }
+  if (!Number.isFinite(value)) {
+    throw new RangeError('UiProgress value must be null or a finite number.')
+  }
+
+  const normalizedValue = Math.min(Math.max(value, 0), max)
+  return {
+    value: normalizedValue,
+    percentage: (normalizedValue / max) * 100,
+  }
+}
+
+export function assertProgressLabel(label: string): void {
+  if (hasText(label)) return
+  throw new Error('UiProgress requires a non-empty accessible label.')
+}
diff --git a/src/components/UI/primitives/types.ts b/src/components/UI/primitives/types.ts
new file mode 100644
index 00000000..e5fcfc0e
--- /dev/null
+++ b/src/components/UI/primitives/types.ts
@@ -0,0 +1,9 @@
+export type UiTone = 'primary' | 'neutral' | 'success' | 'warning' | 'danger' | 'info'
+
+export type UiSize = 'xs' | 'sm' | 'md' | 'lg' | 'xl'
+
+export type UiButtonVariant = 'solid' | 'soft' | 'outline' | 'ghost' | 'link'
+
+export type UiBadgeVariant = 'solid' | 'soft' | 'outline' | 'subtle'
+
+export type UiTooltipPlacement = 'top' | 'right' | 'bottom' | 'left'
diff --git a/src/components/common/Settings/SettingsDialogShell.vue b/src/components/common/Settings/SettingsDialogShell.vue
index 9ad8224d..61c80d52 100644
--- a/src/components/common/Settings/SettingsDialogShell.vue
+++ b/src/components/common/Settings/SettingsDialogShell.vue
@@ -1,6 +1,7 @@
 <script setup lang="ts">
 import { computed } from 'vue'
 import { useI18n } from 'vue-i18n'
+import { UiIcon, UiIconButton } from '@/components/UI/primitives'
 import { PageTabs } from '@/components/navigation'
 
 export interface SettingsDialogTab {
@@ -42,20 +43,13 @@ const currentTab = computed({
           <div class="flex items-center justify-between">
             <div class="flex items-center gap-3">
               <div class="flex h-8 w-8 items-center justify-center rounded-lg bg-primary-600 dark:bg-primary-500">
-                <UIcon name="i-heroicons-cog-6-tooth" class="h-4 w-4 text-white" />
+                <UiIcon name="i-heroicons-cog-6-tooth" size="md" class="text-white" />
               </div>
               <h2 class="text-lg font-semibold text-gray-900 dark:text-white">
                 {{ t('settings.title') }}
               </h2>
             </div>
-            <UButton
-              icon="i-heroicons-x-mark"
-              color="neutral"
-              variant="ghost"
-              size="sm"
-              :aria-label="t('common.close')"
-              @click="emit('update:open', false)"
-            />
+            <UiIconButton icon="i-heroicons-x-mark" :label="t('common.close')" @click="emit('update:open', false)" />
           </div>
           <PageTabs v-model="currentTab" class="mt-4 pb-3" :items="tabs" />
         </div>
diff --git a/src/components/navigation/NavigationTabsBase.vue b/src/components/navigation/NavigationTabsBase.vue
index 7733ba00..d597a517 100644
--- a/src/components/navigation/NavigationTabsBase.vue
+++ b/src/components/navigation/NavigationTabsBase.vue
@@ -1,6 +1,7 @@
 <script setup lang="ts">
 import { ref, computed, watch, onMounted, nextTick } from 'vue'
 import { useRoute, useRouter } from 'vue-router'
+import { UiIcon } from '@/components/UI/primitives'
 import type { NavigationTabItem } from './types'
 
 interface Props {
@@ -129,7 +130,7 @@ watch(
         ]"
         @click="activeTab = tab.id"
       >
-        <UIcon v-if="tab.icon" :name="tab.icon" :class="size === 'sm' ? 'h-3.5 w-3.5' : 'h-4 w-4'" />
+        <UiIcon v-if="tab.icon" :name="tab.icon" :size="size === 'sm' ? 'sm' : 'md'" />
         {{ tab.label }}
       </button>
       <div class="absolute bg-primary-500 transition-all duration-300 ease-out" :style="indicatorStyle" />
diff --git a/src/components/navigation/PageTabs.vue b/src/components/navigation/PageTabs.vue
index 4c8554b8..84ce6f96 100644
--- a/src/components/navigation/PageTabs.vue
+++ b/src/components/navigation/PageTabs.vue
@@ -1,5 +1,6 @@
 <script setup lang="ts">
 import { RouterLink, type RouteLocationRaw } from 'vue-router'
+import { UiIcon } from '@/components/UI/primitives'
 import type { NavigationTabItem } from './types'
 
 interface PageTabItem extends NavigationTabItem {
@@ -48,7 +49,7 @@ function selectItem(item: PageTabItem): void {
           :aria-pressed="item.to ? undefined : modelValue === item.id"
           @click="selectItem(item)"
         >
-          <UIcon v-if="item.icon" :name="item.icon" class="h-3.5 w-3.5" />
+          <UiIcon v-if="item.icon" :name="item.icon" size="sm" />
           <span>{{ item.label }}</span>
         </component>
       </div>