Search: AI transparency strip surfaces the prompt and caveat

- Adds `AiTransparencyStrip.svelte` between the mode chips and filter chips. It shows the natural-language prompt, the AI's caveat if any, and a disabled "Refine…" button with the tooltip `Coming soon: chat back to the agent`. The Refine button parallels the Content mode chip's visible-disabled treatment; no keyboard shortcut is wired.
- Stores the original prompt and caveat in `search-state.svelte.ts` as `lastAiPrompt` / `lastAiCaveat`. `executeAiSearch` captures the prompt BEFORE the IPC call so the strip survives a failed translation. `executeSearch(fromAiTranslation=false)` clears both fields, hiding the strip on any non-AI run. `clearSearchState` (⌘N) clears them too.
- Removes the inline `.caveat-row` / `.ai-status` / `.ai-error` divs and the now-dead `getAiStatus` / `getCaveat` / `setAiStatus` / `setCaveat` accessors in the state module.
- New Vitest coverage: behavior, a11y, and SearchDialog lifecycle (strip appears on AI run, hides on ⌘N, hides on filename/regex run).
- Real-AI verified via the dev app + OpenAI `gpt-5.5`: caveat strip showed "No filename filter — results may be very broad. Add a name or file type to narrow." for the prompt "large files".

Author: vdavid

apps/desktop/src/lib/search/AiTransparencyStrip.a11y.test.ts

@@ -0,0 +1,44 @@
+/**
+ * Tier-3 a11y tests for `AiTransparencyStrip.svelte`.
+ *
+ * Pins that the strip is axe-clean with and without a caveat, and that the disabled "Refine…"
+ * button doesn't trip nested-interactive or hidden-content rules.
+ */
+
+import { describe, it } from 'vitest'
+import { mount, tick, type ComponentProps } from 'svelte'
+import AiTransparencyStrip from './AiTransparencyStrip.svelte'
+import { expectNoA11yViolations } from '$lib/test-a11y'
+
+type Props = ComponentProps<typeof AiTransparencyStrip>
+
+function baseProps(overrides: Partial<Props> = {}): Props {
+  return {
+    aiPrompt: 'screenshots from this week',
+    caveat: '',
+    ...overrides,
+  }
+}
+
+describe('AiTransparencyStrip a11y', () => {
+  it('has no a11y violations with a prompt only', async () => {
+    const target = document.createElement('div')
+    document.body.appendChild(target)
+    mount(AiTransparencyStrip, { target, props: baseProps() })
+    await tick()
+    await expectNoA11yViolations(target)
+    target.remove()
+  })
+
+  it('has no a11y violations with a caveat', async () => {
+    const target = document.createElement('div')
+    document.body.appendChild(target)
+    mount(AiTransparencyStrip, {
+      target,
+      props: baseProps({ caveat: "I treated 'big' as larger than 10 MB." }),
+    })
+    await tick()
+    await expectNoA11yViolations(target)
+    target.remove()
+  })
+})

apps/desktop/src/lib/search/AiTransparencyStrip.svelte

@@ -0,0 +1,105 @@
+<script lang="ts">
+    /**
+     * AiTransparencyStrip: shows what the user actually asked the AI, plus the AI's caveat if any,
+     * and a placeholder "Refine…" button for the future chat-back feature.
+     *
+     * Sits between the search bar (and mode chips) and the filter chips. Visible only after an AI
+     * search has run this session; the parent (`SearchDialog.svelte`) clears the state on ⌘N or when
+     * a non-AI search runs, which hides the strip.
+     *
+     * Why this exists: when the AI translates a natural-language prompt, the result populates
+     * `query` and `mode` so the user can see (and iterate on) the translated pattern. The original
+     * prompt would otherwise vanish into the user's memory. The strip surfaces it again, alongside
+     * any caveat the AI returned ("I ignored the file size you mentioned because…"). This is the
+     * "radical transparency" principle from the redesign plan (§2.6).
+     *
+     * The "Refine…" button is intentionally **visible-disabled** with a tooltip. It signals that
+     * a chat-back feature is coming without overpromising. Consistent with the Content mode chip's
+     * disabled-with-tooltip treatment; neither has a keyboard shortcut wired.
+     */
+    import { tooltip } from '$lib/tooltip/tooltip'
+
+    interface Props {
+        /** The natural-language prompt the user typed, before AI translated it. */
+        aiPrompt: string
+        /** Optional caveat returned by the AI translator. Empty string hides the caveat row. */
+        caveat: string
+    }
+
+    const { aiPrompt, caveat }: Props = $props()
+</script>
+
+<div class="ai-transparency-strip" aria-label="Last AI search prompt">
+    <div class="strip-text">
+        <p class="ai-prompt">{aiPrompt}</p>
+        {#if caveat}
+            <p class="ai-caveat">{caveat}</p>
+        {/if}
+    </div>
+    <button
+        type="button"
+        class="refine-button"
+        disabled
+        aria-label="Refine the AI search (coming soon)"
+        use:tooltip={'Coming soon: chat back to the agent'}
+    >
+        Refine…
+    </button>
+</div>
+
+<style>
+    .ai-transparency-strip {
+        display: flex;
+        align-items: flex-start;
+        gap: var(--spacing-md);
+        padding: var(--spacing-sm) var(--spacing-lg);
+        background: var(--color-bg-primary);
+    }
+
+    .strip-text {
+        flex: 1;
+        min-width: 0;
+        display: flex;
+        flex-direction: column;
+        gap: var(--spacing-xxs);
+    }
+
+    .ai-prompt {
+        margin: 0;
+        color: var(--color-text-secondary);
+        font-size: var(--font-size-sm);
+        line-height: 1.3;
+        overflow: hidden;
+        white-space: nowrap;
+        text-overflow: ellipsis;
+    }
+
+    .ai-caveat {
+        margin: 0;
+        color: var(--color-text-tertiary);
+        font-size: var(--font-size-sm);
+        font-style: italic;
+        line-height: 1.3;
+        overflow: hidden;
+        white-space: nowrap;
+        text-overflow: ellipsis;
+    }
+
+    .refine-button {
+        flex-shrink: 0;
+        padding: var(--spacing-xxs) var(--spacing-sm);
+        font-size: var(--font-size-sm);
+        font-weight: 500;
+        line-height: 1;
+        color: var(--color-text-secondary);
+        background: transparent;
+        border: 1px solid var(--color-border);
+        border-radius: var(--radius-sm);
+        white-space: nowrap;
+    }
+
+    .refine-button:disabled {
+        opacity: 0.5;
+        cursor: not-allowed;
+    }
+</style>

apps/desktop/src/lib/search/AiTransparencyStrip.svelte.test.ts

@@ -0,0 +1,78 @@
+/**
+ * Behavior tests for `AiTransparencyStrip.svelte`.
+ *
+ * Pins:
+ *   - The original prompt is rendered.
+ *   - The caveat is rendered when present and hidden when empty.
+ *   - The "Refine…" button is disabled and carries the "Coming soon" tooltip.
+ */
+
+import { describe, it, expect, vi } from 'vitest'
+import { mount, tick } from 'svelte'
+import AiTransparencyStrip from './AiTransparencyStrip.svelte'
+
+function setup(props: { aiPrompt: string; caveat: string }): { target: HTMLDivElement; cleanup: () => void } {
+  const target = document.createElement('div')
+  document.body.appendChild(target)
+  mount(AiTransparencyStrip, { target, props })
+  return {
+    target,
+    cleanup: () => {
+      target.remove()
+    },
+  }
+}
+
+describe('AiTransparencyStrip', () => {
+  it('renders the original AI prompt', async () => {
+    const { target, cleanup } = setup({ aiPrompt: 'screenshots from this week', caveat: '' })
+    await tick()
+    const prompt = target.querySelector('.ai-prompt')
+    expect(prompt?.textContent).toBe('screenshots from this week')
+    cleanup()
+  })
+
+  it('renders the caveat when present', async () => {
+    const { target, cleanup } = setup({
+      aiPrompt: 'big PDFs',
+      caveat: "I treated 'big' as larger than 10 MB.",
+    })
+    await tick()
+    const caveat = target.querySelector('.ai-caveat')
+    expect(caveat?.textContent).toBe("I treated 'big' as larger than 10 MB.")
+    cleanup()
+  })
+
+  it('does not render the caveat row when caveat is empty', async () => {
+    const { target, cleanup } = setup({ aiPrompt: 'screenshots', caveat: '' })
+    await tick()
+    expect(target.querySelector('.ai-caveat')).toBeNull()
+    cleanup()
+  })
+
+  it('renders a disabled "Refine…" button', async () => {
+    const { target, cleanup } = setup({ aiPrompt: 'photos', caveat: '' })
+    await tick()
+    const button = target.querySelector<HTMLButtonElement>('.refine-button')
+    expect(button).not.toBeNull()
+    expect(button?.disabled).toBe(true)
+    expect(button?.textContent.trim()).toBe('Refine…')
+    cleanup()
+  })
+
+  it('communicates "coming soon" via the Refine button aria-label and use:tooltip text', async () => {
+    vi.useFakeTimers()
+    const { target, cleanup } = setup({ aiPrompt: 'photos', caveat: '' })
+    await tick()
+    const button = target.querySelector<HTMLButtonElement>('.refine-button')
+    // aria-label is the always-available accessible signal that the control is a placeholder.
+    expect(button?.getAttribute('aria-label')).toMatch(/coming soon/i)
+    // The use:tooltip action stages its content on mouseenter behind a 400 ms delay.
+    button?.dispatchEvent(new MouseEvent('mouseenter', { bubbles: true }))
+    vi.advanceTimersByTime(500)
+    const tip = document.body.querySelector('[role="tooltip"]')
+    expect(tip?.textContent).toMatch(/coming soon: chat back to the agent/i)
+    vi.useRealTimers()
+    cleanup()
+  })
+})

apps/desktop/src/lib/search/CLAUDE.md

@@ -11,40 +11,47 @@ chip row and path-pill column landing in later milestones.
 
 ## Files
 
-| File                               | Purpose                                                                                      |
-| ---------------------------------- | -------------------------------------------------------------------------------------------- |
-| `SearchDialog.svelte`              | Orchestrator: overlay, mount/unmount, keyboard dispatch, search execution, state wiring      |
-| `SearchBar.svelte`                 | Unified query input: one `<input>` for AI / filename / regex, placeholder updates per mode   |
-| `SearchModeChips.svelte`           | Mode chip row below the bar: AI / Filename / Content (disabled) / Regex, arrow-key navigable |
-| `SearchFilterChips.svelte`         | Filter chip strip (Size, Modified, Search in) plus Add filter dropdown. Each opens a popover |
-| `FilterChip.svelte`                | Single chip: default/configured states, `×` clear, Backspace clear, aria-expanded            |
-| `FilterChipPopover.svelte`         | Generic popover: frosted-glass, auto-flip, focus trap, Esc closes without disrupting dialog  |
-| `filter-chip-state.ts`             | Pure helpers: `deriveSizeChip`, `deriveDateChip`, `deriveScopeChip` (testable in isolation)  |
-| `SearchResults.svelte`             | Column headers + results list + all states (loading, empty, populated) + status bar          |
-| `search-state.svelte.ts`           | Module-level `$state` for query fields, results, index readiness, AI state                   |
-| `search-state.test.ts`             | Vitest tests for state helpers (`parseSizeToBytes`, `buildSearchQuery`, etc.)                |
-| `filter-chip-state.test.ts`        | Default → configured → cleared rules for each filter chip's display summary                  |
-| `SearchBar.svelte.test.ts`         | Per-mode placeholder, value mirror, `onInput` callback                                       |
-| `SearchModeChips.svelte.test.ts`   | Chip set, active marker, click + keyboard activation, focus motion (skipping Content)        |
-| `SearchFilterChips.svelte.test.ts` | Chip rendering, `×` and Backspace clear, popover open/close, Add filter list, scope behavior |
-| `SearchDialog.svelte.test.ts`      | `⌘N` clears, close+reopen preserves, `⌘1`/`⌘2`/`⌘3` mode switch, `⌘Enter` triggers AI        |
-| `SearchDialog.a11y.test.ts`        | Tier-3 axe-core audit across loading / index-ready / AI-on macro-states                      |
-| `SearchFilterChips.a11y.test.ts`   | Tier-3 axe-core audit across default, configured, disabled, and open-popover states          |
-| `SearchResults.a11y.test.ts`       | Tier-3 axe-core audit across result states                                                   |
-
-## State shape (post-M2)
+| File                                 | Purpose                                                                                                   |
+| ------------------------------------ | --------------------------------------------------------------------------------------------------------- |
+| `SearchDialog.svelte`                | Orchestrator: overlay, mount/unmount, keyboard dispatch, search execution, state wiring                   |
+| `SearchBar.svelte`                   | Unified query input: one `<input>` for AI / filename / regex, placeholder updates per mode                |
+| `SearchModeChips.svelte`             | Mode chip row below the bar: AI / Filename / Content (disabled) / Regex, arrow-key navigable              |
+| `AiTransparencyStrip.svelte`         | Strip below the chip row showing the original AI prompt, the caveat, and a disabled Refine button         |
+| `SearchFilterChips.svelte`           | Filter chip strip (Size, Modified, Search in) plus Add filter dropdown. Each opens a popover              |
+| `FilterChip.svelte`                  | Single chip: default/configured states, `×` clear, Backspace clear, aria-expanded                         |
+| `FilterChipPopover.svelte`           | Generic popover: frosted-glass, auto-flip, focus trap, Esc closes without disrupting dialog               |
+| `filter-chip-state.ts`               | Pure helpers: `deriveSizeChip`, `deriveDateChip`, `deriveScopeChip` (testable in isolation)               |
+| `SearchResults.svelte`               | Column headers + results list + all states (loading, empty, populated) + status bar                       |
+| `search-state.svelte.ts`             | Module-level `$state` for query fields, results, index readiness, AI state                                |
+| `search-state.test.ts`               | Vitest tests for state helpers (`parseSizeToBytes`, `buildSearchQuery`, etc.)                             |
+| `filter-chip-state.test.ts`          | Default → configured → cleared rules for each filter chip's display summary                               |
+| `SearchBar.svelte.test.ts`           | Per-mode placeholder, value mirror, `onInput` callback                                                    |
+| `SearchModeChips.svelte.test.ts`     | Chip set, active marker, click + keyboard activation, focus motion (skipping Content)                     |
+| `SearchFilterChips.svelte.test.ts`   | Chip rendering, `×` and Backspace clear, popover open/close, Add filter list, scope behavior              |
+| `AiTransparencyStrip.svelte.test.ts` | Renders prompt, renders caveat when set, Refine button is disabled with Coming soon tooltip               |
+| `SearchDialog.svelte.test.ts`        | `⌘N` clears, close+reopen preserves, `⌘1`/`⌘2`/`⌘3` mode switch, `⌘Enter` triggers AI, AI strip lifecycle |
+| `SearchDialog.a11y.test.ts`          | Tier-3 axe-core audit across loading / index-ready / AI-on macro-states                                   |
+| `SearchFilterChips.a11y.test.ts`     | Tier-3 axe-core audit across default, configured, disabled, and open-popover states                       |
+| `AiTransparencyStrip.a11y.test.ts`   | Tier-3 axe-core audit for prompt-only and prompt-plus-caveat states                                       |
+| `SearchResults.a11y.test.ts`         | Tier-3 axe-core audit across result states                                                                |
+
+## State shape (post-M4)
 
 The user's typed text and the active mode are one model:
 
 ```ts
 let query = $state('') // The text in the bar
 let mode = $state<SearchMode>('filename') // 'ai' | 'filename' | 'regex'
+let lastAiPrompt = $state<string | null>(null) // The natural-language prompt before AI overwrites `query`
+let lastAiCaveat = $state<string | null>(null) // The AI translator's caveat (or null)
 ```
 
-`buildSearchQuery()` reads both: `mode === 'regex'` produces `patternType: 'regex'`, anything else produces
-`patternType: 'glob'`. AI mode is only ever invoked via `executeAiSearch()`, which calls `translateSearchQuery` and then
-overwrites `query` + `mode` with the AI's result (so the user sees what was searched). M4 will surface the original
-prompt in a transparency strip; for M2 it lives only in the user's memory.
+`buildSearchQuery()` reads `query` + `mode`: `mode === 'regex'` produces `patternType: 'regex'`, anything else produces
+`patternType: 'glob'`. AI mode is only ever invoked via `executeAiSearch()`, which (1) captures the user's prompt into
+`lastAiPrompt`, (2) calls `translateSearchQuery`, (3) overwrites `query` + `mode` with the AI's result so the user can
+see and iterate on the translated pattern, and (4) sets `lastAiCaveat` from the result. The `AiTransparencyStrip` is
+visible whenever `lastAiPrompt` is non-null; it clears on `⌘N` (via `clearSearchState`) and on any successful non-AI
+search (`executeSearch(fromAiTranslation = false)`).
 
 There is **no `aiPrompt` state and no `namePattern` state**. M2 deleted both. Anywhere the old code read `aiPrompt` or
 `namePattern`, the new code reads `query`. Anywhere the old code branched on `patternType`, the new code branches on
@@ -120,9 +127,20 @@ a message ("Drive index not ready...") with scan progress if available. Inputs a
 extracts keywords, Rust builds the query deterministically), then runs `executeSearch()`. No preflight, no refinement
 pass. The previous two-pass system caused ~15% regressions; deterministic structure means there's nothing to refine.
 
-**AI overwrites the bar**: After AI translates, the bar shows the AI's translated pattern (filename / regex), and `mode`
-flips accordingly. The user sees what was searched and can keep iterating. The original natural-language prompt is
-preserved only in the user's memory until M4 ships the transparency strip.
+**AI overwrites the bar; the strip preserves the prompt**: After AI translates, the bar shows the AI's translated
+pattern (filename / regex), and `mode` flips accordingly. The user sees what was searched and can keep iterating. The
+original natural-language prompt and the AI's caveat are surfaced in the `AiTransparencyStrip` below the chip row. The
+strip is the source of truth for "what did I ask the AI?" once the bar has been overwritten. Lifecycle:
+
+- `executeAiSearch(trimmed)` sets `lastAiPrompt = trimmed` BEFORE calling `translateSearchQuery`. The capture is
+  unconditional: even if the IPC fails, the user still sees what they asked.
+- After the translation succeeds, `lastAiCaveat = translateResult.caveat ?? null`.
+- `executeSearch(fromAiTranslation: boolean)` clears both fields when `fromAiTranslation` is false. `executeAiSearch`
+  passes `true`, so the AI flow's tail (`executeSearch(true)`) leaves the strip intact.
+- `clearSearchState()` (called by `⌘N`) clears both fields.
+
+The disabled "Refine…" button on the strip is the placeholder for the chat-back UX. No keyboard shortcut is wired (same
+contract as the Content mode chip: visible-disabled with an explanatory tooltip is fine; shortcut-but-no-op is hostile).
 
 **Auto mode fallback when AI gets disabled mid-session**: If the AI provider is switched off while the dialog is open
 and the active mode is `ai`, the dialog quietly flips to `filename`. The user wouldn't be able to run a search
@@ -175,9 +193,9 @@ close + reopen into a lost-work moment. The only sanctioned reset path is `⌘N`
 state from a lifecycle hook, you probably want a user-initiated action instead.
 
 **Gotcha**: The AI's translation overwrites `query` and `mode`. **Why**: We want the bar to show what was searched, not
-the natural-language prompt. Until M4 ships the transparency strip, the original prompt is only in the user's memory.
-Anyone building on top of this should not assume `query` still contains the user's natural-language input after an AI
-run.
+the natural-language prompt. The original prompt is preserved separately in `lastAiPrompt` (set by `executeAiSearch`
+before the IPC call) so the `AiTransparencyStrip` can render it. Anyone building on top of this should not assume
+`query` still contains the user's natural-language input after an AI run; use `getLastAiPrompt()` instead.
 
 ## References