diff --git a/src/cli/agent-session-search-format.test.ts b/src/cli/agent-session-search-format.test.ts
index 27f0a28924c..0b0157c4736 100644
--- a/src/cli/agent-session-search-format.test.ts
+++ b/src/cli/agent-session-search-format.test.ts
@@ -33,7 +33,7 @@ function makeHit(overrides: Partial<AiVaultSearchHit> = {}): AiVaultSearchHit {
     evidence: {
       role: 'assistant',
       timestamp: '2026-09-01T11:29:00.000Z',
-      snippet: 'the [strict] [mode] guard fires\ntwice',
+      snippet: 'the [[strict]] [[mode]] guard fires\ntwice',
       ...overrides.evidence
     },
     ...overrides
@@ -64,6 +64,28 @@ afterEach(() => {
 })
 
 describe('formatAgentSessionSearch', () => {
+  it('strips terminal escape sequences and control bytes from transcript fields', () => {
+    const output = format(
+      makeResult({
+        hits: [
+          makeHit({
+            title: 'Fix \u001b]52;c;Zm9v\u0007 clipboard',
+            evidence: {
+              role: 'tool',
+              timestamp: null,
+              snippet: 'ran \u001b[31m[[rm]]\u001b[0m -rf\u0000 /tmp'
+            }
+          })
+        ]
+      }),
+      'rm'
+    )
+    expect(output).not.toContain('\u001b')
+    expect(output).not.toContain('\u0000')
+    expect(output).toContain('Fix  clipboard')
+    expect(output).toContain('ran [[rm]] -rf /tmp')
+  })
+
   it('reports no match with the query when there are no hits', () => {
     const output = format(makeResult({ hits: [] }), 'kernel panic')
     expect(output.split('\n')[0]).toBe('No sessions match "kernel panic".')
@@ -79,7 +101,7 @@ describe('formatAgentSessionSearch', () => {
 
   it('renders the evidence role glyph and a single-line snippet', () => {
     const evidence = format(makeResult()).split('\n')[1]
-    expect(evidence).toBe('    agent ▸ the [strict] [mode] guard fires twice')
+    expect(evidence).toBe('    agent ▸ the [[strict]] [[mode]] guard fires twice')
   })
 
   it('labels each evidence role distinctly', () => {
diff --git a/src/cli/agent-session-search-format.ts b/src/cli/agent-session-search-format.ts
index 96e11e85912..5d1f3a3c0b0 100644
--- a/src/cli/agent-session-search-format.ts
+++ b/src/cli/agent-session-search-format.ts
@@ -1,3 +1,7 @@
+import {
+  stripAnsiEscapeSequences,
+  TERMINAL_CONTROL_CHARACTER_PATTERN
+} from '../shared/ansi-escape-sequences'
 import { basename } from 'node:path'
 import type { AiVaultSearchIndexStatus } from '../shared/ai-vault-search-settings'
 import { aiVaultAgentLabel } from '../shared/ai-vault-types'
@@ -41,13 +45,19 @@ function projectLabel(hit: AiVaultSearchHit): string {
   return hit.branch ? `${cwd} · ${hit.branch}` : cwd
 }
 
+// Why: transcript text reaches the terminal verbatim; an OSC 52 or cursor
+// sequence inside a tool log would otherwise execute on the user's terminal.
+function terminalSafe(value: string): string {
+  return stripAnsiEscapeSequences(value).replace(TERMINAL_CONTROL_CHARACTER_PATTERN, '')
+}
+
 function formatHit(index: number, hit: AiVaultSearchHit): string {
-  const header = `${String(index + 1).padStart(2)}. ${hit.title}`
-  const meta = `${aiVaultAgentLabel(hit.agent)} · ${projectLabel(hit)} · ${relativeAge(hit.updatedAt)}`
+  const header = `${String(index + 1).padStart(2)}. ${terminalSafe(hit.title)}`
+  const meta = `${aiVaultAgentLabel(hit.agent)} · ${terminalSafe(projectLabel(hit))} · ${relativeAge(hit.updatedAt)}`
   const evidence = hit.evidence.snippet
-    ? `    ${ROLE_LABEL[hit.evidence.role]} ▸ ${hit.evidence.snippet.replaceAll('\n', ' ')}`
+    ? `    ${ROLE_LABEL[hit.evidence.role]} ▸ ${terminalSafe(hit.evidence.snippet).replaceAll('\n', ' ')}`
     : null
-  const resume = `    resume: ${hit.resumeCommand}${hit.cwd ? `  (cwd ${hit.cwd})` : ''}`
+  const resume = `    resume: ${terminalSafe(hit.resumeCommand)}${hit.cwd ? `  (cwd ${terminalSafe(hit.cwd)})` : ''}`
   return [`${header}    ${meta}`, evidence, resume].filter(Boolean).join('\n')
 }
 
diff --git a/src/cli/handlers/search.test.ts b/src/cli/handlers/search.test.ts
index 0dc82c3fb32..41321e6f38f 100644
--- a/src/cli/handlers/search.test.ts
+++ b/src/cli/handlers/search.test.ts
@@ -135,6 +135,23 @@ describe('orca search --agent-session', () => {
     expect(callMock).not.toHaveBeenCalled()
   })
 
+  it('rejects non-ISO dates that Date.parse would accept', async () => {
+    for (const since of ['08/01/2026', 'Sat, 01 Aug 2026 00:00:00 GMT']) {
+      const error = await runSearch({ 'agent-session': 'q', since }).catch(
+        (caught: unknown) => caught
+      )
+      expect((error as RuntimeClientError).code).toBe('invalid_argument')
+    }
+    expect(callMock).not.toHaveBeenCalled()
+  })
+
+  it('leaves a ~user path alone instead of splicing HOME into it', async () => {
+    vi.stubEnv('HOME', '/home/tester')
+    await runSearch({ 'agent-session': 'q', path: '~other/repo' })
+    expect(searchParams().scopePaths).toEqual(['~other/repo'])
+    vi.unstubAllEnvs()
+  })
+
   it('normalizes --since to an ISO timestamp', async () => {
     await runSearch({ 'agent-session': 'q', since: '2026-08-01T00:00:00+02:00' })
     expect(searchParams().since).toBe('2026-07-31T22:00:00.000Z')
diff --git a/src/cli/handlers/search.ts b/src/cli/handlers/search.ts
index e968840ad1d..6bda030c7b4 100644
--- a/src/cli/handlers/search.ts
+++ b/src/cli/handlers/search.ts
@@ -35,12 +35,25 @@ function parseAgents(flags: Map<string, string | boolean>): AiVaultAgent[] | und
   return agents
 }
 
+const ISO_8601 =
+  /^\d{4}-\d{2}-\d{2}(?:[T ]\d{2}:\d{2}(?::\d{2}(?:\.\d{1,9})?)?(?:Z|[+-]\d{2}:?\d{2})?)?$/
+
+/** `~` and `~/x` are the home directory; `~other/x` is left for the host to resolve. */
+function expandHomePath(value: string): string {
+  const home = process.env.HOME
+  if (!home || (value !== '~' && !value.startsWith('~/'))) {
+    return value
+  }
+  return `${home}${value.slice(1)}`
+}
+
 function parseSince(flags: Map<string, string | boolean>): string | undefined {
   const value = getOptionalStringFlag(flags, 'since')
   if (value === undefined) {
     return undefined
   }
-  const parsed = Date.parse(value)
+  // Why: Date.parse also accepts `08/01/2026` and RFC 2822; the flag documents ISO 8601.
+  const parsed = ISO_8601.test(value) ? Date.parse(value) : Number.NaN
   if (!Number.isFinite(parsed)) {
     throw new RuntimeClientError('invalid_argument', '--since must be an ISO 8601 timestamp.')
   }
@@ -78,9 +91,7 @@ export const SEARCH_HANDLERS: Record<string, CommandHandler> = {
         'Missing --agent-session <query>. Example: orca search --agent-session "strict mode violation"'
       )
     }
-    const scopePaths = getRepeatedStringFlag(flags, 'path').map((value) =>
-      value.startsWith('~') ? value.replace(/^~/, process.env.HOME ?? '~') : value
-    )
+    const scopePaths = getRepeatedStringFlag(flags, 'path').map(expandHomePath)
     const result = await client.call<AiVaultSearchResult>('aiVault.searchSessions', {
       query,
       limit: getOptionalPositiveIntegerFlag(flags, 'limit'),
diff --git a/src/main/ai-vault-search/session-search-consent.test.ts b/src/main/ai-vault-search/session-search-consent.test.ts
index 10927da8f8a..5ab4220b77e 100644
--- a/src/main/ai-vault-search/session-search-consent.test.ts
+++ b/src/main/ai-vault-search/session-search-consent.test.ts
@@ -2,8 +2,26 @@ import { existsSync } from 'node:fs'
 import { mkdir, mkdtemp, rm, utimes, writeFile } from 'node:fs/promises'
 import { tmpdir } from 'node:os'
 import { join } from 'node:path'
-import { afterEach, beforeEach, describe, expect, it } from 'vitest'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+
+// Why: the backfill's first await; failing it once is the cheapest way to make
+// a whole pass throw without touching the transcripts on disk.
+let failNextParseCacheLoad = false
+vi.mock('../ai-vault/session-parse-cache-persistence', async (importOriginal) => {
+  const actual = await importOriginal<typeof ParseCachePersistence>()
+  return {
+    ...actual,
+    ensureSessionParseCacheLoaded: (): Promise<void> => {
+      if (failNextParseCacheLoad) {
+        failNextParseCacheLoad = false
+        return Promise.reject(new Error('parse cache unavailable'))
+      }
+      return actual.ensureSessionParseCacheLoaded()
+    }
+  }
+})
 import { getSessionSearchIndexSink } from '../ai-vault/session-search-capture'
+import type * as ParseCachePersistence from '../ai-vault/session-parse-cache-persistence'
 import { resetSessionParseCacheForTests } from '../ai-vault/session-scanner-parse-cache'
 import { isolatedScanRoots, jsonLines } from '../ai-vault/session-scanner-test-fixtures'
 import { SessionSearchService, type SessionSearchScanRoots } from './session-search-service'
@@ -158,6 +176,35 @@ describe('SessionSearchService consent gate', () => {
     expect(existsSync(`${databasePath}-wal`)).toBe(false)
   })
 
+  it('retries a backfill that failed instead of memoizing the failure', async () => {
+    const { roots, databasePath } = await scanRoots()
+    await writeClaudeTranscript(roots, 'retry-session', 'the vacuum quota never settles')
+
+    const service = makeService(databasePath, { enabled: true, historyDays: null })
+    failNextParseCacheLoad = true
+    await service.ensureBackfill(roots)
+    expect(service.coverage().sessionsIndexed).toBe(0)
+    expect(service.coverage().backfill).toBe('idle')
+
+    await service.ensureBackfill(roots)
+    const result = await service.search({ query: 'vacuum', refresh: false }, roots)
+    expect(result.hits.map((hit) => hit.sessionId)).toContain('retry-session')
+  })
+
+  it('re-enumerates when the history bound is widened after a finished backfill', async () => {
+    const { roots, databasePath } = await scanRoots()
+    await writeClaudeTranscript(roots, 'recent-session', 'the vacuum quota never settles', 1)
+    await writeClaudeTranscript(roots, 'ancient-session', 'the vacuum quota never settles', 120)
+
+    const service = makeService(databasePath, { enabled: true, historyDays: 30 })
+    await service.ensureBackfill(roots)
+    await service.configure({ enabled: true, historyDays: null }, roots)
+    await service.ensureBackfill(roots)
+
+    const result = await service.search({ query: 'vacuum', refresh: false }, roots)
+    expect(result.hits.map((hit) => hit.sessionId)).toContain('ancient-session')
+  })
+
   it('skips transcripts older than the history bound', async () => {
     const { roots, databasePath } = await scanRoots()
     await writeClaudeTranscript(roots, 'recent-session', 'the vacuum quota never settles', 1)
diff --git a/src/main/ai-vault-search/session-search-enablement.test.ts b/src/main/ai-vault-search/session-search-enablement.test.ts
index 3dc3ea8fab7..887b3616c2c 100644
--- a/src/main/ai-vault-search/session-search-enablement.test.ts
+++ b/src/main/ai-vault-search/session-search-enablement.test.ts
@@ -110,4 +110,13 @@ describe('readAiVaultSearchIndexStatus', () => {
 
     expect(readAiVaultSearchIndexStatus().indexSizeBytes).toBe(123)
   })
+
+  it('treats a leftover sidecar without the database as no index', async () => {
+    const userData = await makeUserDataDir()
+    initSessionSearchPaths(userData)
+    await mkdir(join(userData, 'ai-vault-search'), { recursive: true })
+    await writeFile(join(userData, 'ai-vault-search', 'index.sqlite-wal'), 'y'.repeat(23))
+
+    expect(readAiVaultSearchIndexStatus().indexSizeBytes).toBeNull()
+  })
 })
diff --git a/src/main/ai-vault-search/session-search-enablement.ts b/src/main/ai-vault-search/session-search-enablement.ts
index 19a493df4ee..fec8207f54e 100644
--- a/src/main/ai-vault-search/session-search-enablement.ts
+++ b/src/main/ai-vault-search/session-search-enablement.ts
@@ -35,9 +35,19 @@ export function applyAiVaultSearchSettings(
     return Promise.resolve(null)
   }
   const policy: AiVaultSearchSettings = resolveAiVaultSearchSettings(settings)
-  return configureAiVaultSearch({ databasePath, ...policy }, { clearIndex: options.clearIndex })
+  // Why: each call resolves scan roots before it reaches the scanner, so two
+  // overlapping toggles could land out of order; apply them one after another.
+  const applied = applyChain
+    .catch(() => undefined)
+    .then(() =>
+      configureAiVaultSearch({ databasePath, ...policy }, { clearIndex: options.clearIndex })
+    )
+  applyChain = applied
+  return applied
 }
 
+let applyChain: Promise<unknown> = Promise.resolve()
+
 export function readAiVaultSearchIndexStatus(): AiVaultSearchIndexStatus {
   return { ...getSessionSearchPolicy(), indexSizeBytes: readAiVaultSearchIndexSizeBytes() }
 }
@@ -76,12 +86,18 @@ export function readAiVaultSearchIndexSizeBytes(): number | null {
   if (!databasePath) {
     return null
   }
-  let total: number | null = null
-  for (const suffix of ['', '-wal', '-shm', '-journal']) {
+  let total: number
+  try {
+    total = statSync(databasePath).size
+  } catch {
+    // Why: a leftover sidecar without the main file is not an index.
+    return null
+  }
+  for (const suffix of ['-wal', '-shm', '-journal']) {
     try {
-      total = (total ?? 0) + statSync(`${databasePath}${suffix}`).size
+      total += statSync(`${databasePath}${suffix}`).size
     } catch {
-      // A missing sidecar is normal; only a missing main file means "no index".
+      // A missing sidecar is normal.
     }
   }
   return total
diff --git a/src/main/ai-vault-search/session-search-query.ts b/src/main/ai-vault-search/session-search-query.ts
index f313a7349ff..6509fcbe6ef 100644
--- a/src/main/ai-vault-search/session-search-query.ts
+++ b/src/main/ai-vault-search/session-search-query.ts
@@ -6,7 +6,9 @@ import type {
 } from '../../shared/ai-vault-search-types'
 import {
   AI_VAULT_SEARCH_LIMIT_DEFAULT,
-  AI_VAULT_SEARCH_LIMIT_MAX
+  AI_VAULT_SEARCH_LIMIT_MAX,
+  AI_VAULT_SEARCH_SNIPPET_MARK_CLOSE,
+  AI_VAULT_SEARCH_SNIPPET_MARK_OPEN
 } from '../../shared/ai-vault-search-types'
 import type { AiVaultAgent } from '../../shared/ai-vault-types'
 import {
@@ -32,6 +34,10 @@ const MESSAGE_CANDIDATE_LIMIT = 600
 // Subtracted per session: `0.02 · ln(1 + messages)`; slightly positive on both eval sets.
 const LENGTH_PRIOR = 0.02
 const SNIPPET_TOKENS = 12
+// Why: single brackets are everywhere in code transcripts (`arr[0]`, regex
+// classes, markdown links) and would read as matches; doubled ones are rare.
+const SNIPPET_MARK_OPEN = AI_VAULT_SEARCH_SNIPPET_MARK_OPEN
+const SNIPPET_MARK_CLOSE = AI_VAULT_SEARCH_SNIPPET_MARK_CLOSE
 
 type MessageRow = {
   rowid: number
@@ -103,7 +109,7 @@ export class SessionSearchQuery {
     }
     const exact = this.retrieveLiteral(plan, retrieval.tier)
     if (exact) {
-      return { hits: this.rollUp(exact.rows, retrieval), route: exact.route }
+      return { hits: this.rollUp(exact.rows, retrieval, plan), route: exact.route }
     }
     // Why: repair runs before the OR fallback, not after it fails; a typo next
     // to a common word would otherwise be masked by the common word's hits.
@@ -115,7 +121,7 @@ export class SessionSearchQuery {
       route: 'or' as const
     }
     return {
-      hits: this.rollUp(result.rows, retrieval),
+      hits: this.rollUp(result.rows, retrieval, effective),
       route: repaired ? (`typo+${result.route}` as AiVaultSearchRoute) : result.route,
       ...(repaired ? { repairedTerms: repaired.body } : {})
     }
@@ -192,7 +198,11 @@ export class SessionSearchQuery {
     }
   }
 
-  private rollUp(rows: MessageRow[], retrieval: Retrieval): AiVaultSearchHit[] {
+  private rollUp(
+    rows: MessageRow[],
+    retrieval: Retrieval,
+    plan: SessionSearchQueryPlan
+  ): AiVaultSearchHit[] {
     const best = new Map<number, MessageRow>()
     for (const row of rows) {
       const current = best.get(row.session_row_id)
@@ -230,20 +240,22 @@ export class SessionSearchQuery {
         evidence: {
           role: message.role as AiVaultSearchHit['evidence']['role'],
           timestamp: message.ts,
-          snippet: this.snippet(table, message.rowid, retrieval.text)
+          snippet: this.snippet(table, message.rowid, plan)
         }
       }))
   }
 
-  private snippet(table: string, rowid: number, query: string): string {
-    const expression = orExpression(planSessionSearchQuery(query).terms)
+  // Why: the snippet must highlight the terms that actually retrieved the row,
+  // so a hit found through typo repair is marked with the repaired terms.
+  private snippet(table: string, rowid: number, plan: SessionSearchQueryPlan): string {
+    const expression = orExpression(plan.terms)
     try {
       // Why: a bound `rowid = ?` or `rowid IN (?)` next to MATCH is silently
       // ignored by the FTS5 planner (it returns the first match); only the
       // subselect form is honoured. Column -1 picks whichever column matched.
       const row = this.db
         .prepare(
-          `SELECT snippet(${table}, -1, '[', ']', '…', ${SNIPPET_TOKENS}) AS s
+          `SELECT snippet(${table}, -1, '${SNIPPET_MARK_OPEN}', '${SNIPPET_MARK_CLOSE}', '…', ${SNIPPET_TOKENS}) AS s
            FROM ${table} WHERE ${table} MATCH ? AND rowid IN (SELECT ?)`
         )
         .get(expression, rowid) as { s: string } | undefined
@@ -261,8 +273,13 @@ export class SessionSearchQuery {
   }
 }
 
+// Why: the desktop IPC forwards its payload unvalidated, so a non-positive
+// limit must be clamped here or `LIMIT -1` / `slice(0, -1)` leak through.
 function resolveLimit(args: AiVaultSearchArgs): number {
-  return Math.min(args.limit ?? AI_VAULT_SEARCH_LIMIT_DEFAULT, AI_VAULT_SEARCH_LIMIT_MAX)
+  const requested = Number.isInteger(args.limit)
+    ? (args.limit as number)
+    : AI_VAULT_SEARCH_LIMIT_DEFAULT
+  return Math.min(Math.max(1, requested), AI_VAULT_SEARCH_LIMIT_MAX)
 }
 
 function sessionFields(session: SessionRow): Omit<AiVaultSearchHit, 'score' | 'evidence'> {
diff --git a/src/main/ai-vault-search/session-search-row-filter.ts b/src/main/ai-vault-search/session-search-row-filter.ts
index d22a26213f2..3e1348d6fbb 100644
--- a/src/main/ai-vault-search/session-search-row-filter.ts
+++ b/src/main/ai-vault-search/session-search-row-filter.ts
@@ -29,10 +29,14 @@ export function sessionRowFilter(
     filter.values.push(args.since)
   }
   if (args.scopePaths && args.scopePaths.length > 0) {
-    filter.conditions.push(`(${args.scopePaths.map(() => '(cwd = ? OR cwd LIKE ?)').join(' OR ')})`)
+    filter.conditions.push(
+      `(${args.scopePaths.map(() => `(${CWD} = ? OR ${CWD} LIKE ? ESCAPE '\\')`).join(' OR ')})`
+    )
     for (const scope of args.scopePaths) {
-      const trimmed = scope.replace(/[\\/]+$/, '')
-      filter.values.push(trimmed, `${trimmed}${trimmed.includes('\\') ? '\\' : '/'}%`)
+      // Same spelling as CWD so a Windows scope matches a POSIX-recorded cwd,
+      // and escaped so `%`/`_` in a folder name cannot widen the match.
+      const normalized = scope.replaceAll('\\', '/').replace(/\/+$/, '')
+      filter.values.push(normalized, `${escapeLike(normalized)}/%`)
     }
   }
   // Operators narrow, never widen: each one is its own ANDed condition on top
diff --git a/src/main/ai-vault-search/session-search-service.ts b/src/main/ai-vault-search/session-search-service.ts
index e4ce5fd9f82..f17fb4e7830 100644
--- a/src/main/ai-vault-search/session-search-service.ts
+++ b/src/main/ai-vault-search/session-search-service.ts
@@ -45,7 +45,38 @@ const REFRESH_RECENT_PER_AGENT = 12
 const BACKFILL_LOAD_PER_CPU_CEILING = 1.5
 const BACKFILL_LOAD_PAUSE_MS = 15_000
 
+/** null (all history) is the widest bound; otherwise more days means wider. */
+function widensHistory(previous: number | null, next: number | null): boolean {
+  if (previous === null) {
+    return false
+  }
+  return next === null || next > previous
+}
+
+// Why: Windows reports a zero load average, so the only signal left is the
+// scanner's own recent CPU share; back off when it has been near a full core.
+const WINDOWS_SELF_CPU_SHARE_CEILING = 0.8
+let lastCpuSample: { usage: NodeJS.CpuUsage; at: number } | null = null
+
+function selfCpuShareSinceLastYield(): number {
+  const now = performance.now()
+  const usage = process.cpuUsage()
+  const previous = lastCpuSample
+  lastCpuSample = { usage, at: now }
+  if (!previous) {
+    return 0
+  }
+  const busyMs = (usage.user - previous.usage.user + usage.system - previous.usage.system) / 1000
+  const elapsedMs = Math.max(1, now - previous.at)
+  return busyMs / elapsedMs
+}
+
 function backfillPauseMs(): number {
+  if (process.platform === 'win32') {
+    return selfCpuShareSinceLastYield() > WINDOWS_SELF_CPU_SHARE_CEILING
+      ? BACKFILL_LOAD_PAUSE_MS
+      : BACKFILL_YIELD_MS
+  }
   const perCpu = loadavg()[0] / Math.max(1, cpus().length)
   return perCpu > BACKFILL_LOAD_PER_CPU_CEILING ? BACKFILL_LOAD_PAUSE_MS : BACKFILL_YIELD_MS
 }
@@ -122,9 +153,14 @@ export class SessionSearchService {
     options: { clearIndex?: boolean } = {}
   ): Promise<AiVaultSearchCoverage> {
     const wasEnabled = this.policy.enabled
+    const previousDays = this.policy.historyDays
     this.policy = { enabled: next.enabled, historyDays: next.historyDays }
     if (options.clearIndex || (wasEnabled && !next.enabled)) {
       await this.stop()
+    } else if (wasEnabled && widensHistory(previousDays, next.historyDays)) {
+      // Why: a finished backfill is memoized; a wider window has files it
+      // skipped, so it has to enumerate again (rows already indexed are reused).
+      await this.stop({ keepStore: true })
     }
     if (options.clearIndex) {
       removeSessionSearchDatabase(this.databasePath)
@@ -146,11 +182,19 @@ export class SessionSearchService {
     }
     if (!this.backfillRun) {
       this.backfillController = new AbortController()
-      this.backfillRun = this.runBackfill(roots, this.backfillController.signal)
-        .catch((error) => console.warn('[ai-vault-search] backfill stopped:', error))
+      const run = this.runBackfill(roots, this.backfillController.signal)
+        .catch((error) => {
+          console.warn('[ai-vault-search] backfill stopped:', error)
+          // Why: a failed pass must not be memoized as done; the next search
+          // gets to try again instead of reporting an incomplete index forever.
+          if (this.backfillRun === run) {
+            this.backfillRun = null
+          }
+        })
         .finally(() => {
           this.backfillController = null
         })
+      this.backfillRun = run
     }
     return this.backfillRun
   }
@@ -173,14 +217,16 @@ export class SessionSearchService {
   }
 
   /** Waits for the aborted backfill so its last parse cannot write to a closed store. */
-  private async stop(): Promise<void> {
+  private async stop(options: { keepStore?: boolean } = {}): Promise<void> {
     this.backfillController?.abort()
     const run = this.backfillRun
     this.backfillRun = null
     if (run) {
       await run.catch(() => undefined)
     }
-    this.closeStore()
+    if (!options.keepStore) {
+      this.closeStore()
+    }
   }
 
   private closeStore(): void {
@@ -206,11 +252,21 @@ export class SessionSearchService {
   }
 
   private async reindexStale(signal?: AbortSignal): Promise<void> {
-    const stale = this.store?.takeStale() ?? []
-    if (stale.length === 0) {
+    const store = this.store
+    const stale = store?.takeStale() ?? []
+    if (stale.length === 0 || !store) {
       return
     }
-    await this.parseAll(stale, signal)
+    try {
+      await this.parseAll(stale, signal)
+    } catch (error) {
+      // Why: a cancelled search (the renderer retires them per keystroke) must
+      // not lose the queue; whatever did not get parsed goes back for next time.
+      for (const candidate of stale) {
+        store.markStale(candidate)
+      }
+      throw error
+    }
   }
 
   /** The retention bound is enforced on enumeration; already-indexed rows survive until a clear. */
diff --git a/src/main/ai-vault-search/session-search-store.test.ts b/src/main/ai-vault-search/session-search-store.test.ts
index 123252da4c7..a049bac475b 100644
--- a/src/main/ai-vault-search/session-search-store.test.ts
+++ b/src/main/ai-vault-search/session-search-store.test.ts
@@ -78,7 +78,7 @@ describe('SessionSearchStore', () => {
       cwd: '/repo/app',
       evidence: { role: 'tool' }
     })
-    expect(literal.hits[0]?.evidence.snippet).toContain('[strict]')
+    expect(literal.hits[0]?.evidence.snippet).toContain('[[strict]]')
     expect(literal.route).toBe('phrase')
 
     // Identifier split: a partial camelCase name still matches.
@@ -202,6 +202,12 @@ describe('SessionSearchStore', () => {
     expect(store.search({ query: 'shared phrase', agents: ['codex'] }).hits).toHaveLength(0)
     expect(store.search({ query: 'shared phrase', scopePaths: ['/repo'] }).hits).toHaveLength(2)
     expect(store.search({ query: 'shared phrase', scopePaths: ['/other'] }).hits).toHaveLength(0)
+    // `_` is a LIKE wildcard; an escaped scope must not match `/repo` through `/r_po`.
+    expect(store.search({ query: 'shared phrase', scopePaths: ['/r_po'] }).hits).toHaveLength(0)
+    expect(store.search({ query: 'shared phrase', scopePaths: ['\\repo\\'] }).hits).toHaveLength(2)
+    // A non-positive limit from an unvalidated caller is clamped, not passed to SQL.
+    expect(store.search({ query: 'shared phrase', limit: -1 }).hits).toHaveLength(1)
+    expect(store.search({ query: 'shared phrase', limit: 0 }).hits).toHaveLength(1)
   })
 
   it('keeps a provider with discovered files and no indexed sessions in coverage', async () => {
diff --git a/src/main/ai-vault-search/session-search-store.ts b/src/main/ai-vault-search/session-search-store.ts
index 960fbda0c1b..a0020cc9a45 100644
--- a/src/main/ai-vault-search/session-search-store.ts
+++ b/src/main/ai-vault-search/session-search-store.ts
@@ -13,6 +13,7 @@ import type {
   SessionSearchIndexUpdate
 } from '../ai-vault/session-search-capture'
 import type { SessionFileCandidate } from '../ai-vault/session-scanner-types'
+import { redactSessionSearchText } from './session-search-redaction'
 import { SessionSearchIndexWriter } from './session-search-index-writer'
 import { SessionSearchQuery } from './session-search-query'
 import { openSessionSearchDatabase } from './session-search-schema'
@@ -177,7 +178,7 @@ export class SessionSearchStore implements SessionSearchIndexSink {
         .prepare(
           'INSERT INTO search_log(ts, query, route, hits, duration_ms) VALUES (?, ?, ?, ?, ?)'
         )
-        .run(new Date().toISOString(), query, route, hits, durationMs)
+        .run(new Date().toISOString(), redactSessionSearchText(query), route, hits, durationMs)
       this.db
         .prepare(
           `DELETE FROM search_log WHERE id <= (
diff --git a/src/main/ai-vault/session-scanner-background.ts b/src/main/ai-vault/session-scanner-background.ts
index 8e88f01af5d..c08025e19dd 100644
--- a/src/main/ai-vault/session-scanner-background.ts
+++ b/src/main/ai-vault/session-scanner-background.ts
@@ -104,7 +104,7 @@ export function readAiVaultSearchCoverageInBackground(
 ): Promise<AiVaultSearchCoverage> {
   return shouldUseAiVaultServiceProcess()
     ? readAiVaultSearchCoverageInService(request, signal)
-    : readAiVaultSearchCoverageInWorker(request)
+    : readAiVaultSearchCoverageInWorker(request, signal)
 }
 
 /** Null when no scanner is running: the next spawn reads the policy from its init payload. */
diff --git a/src/main/ai-vault/session-scanner-cursor-chat-meta.ts b/src/main/ai-vault/session-scanner-cursor-chat-meta.ts
index 3005920ca72..a88ccd5cc59 100644
--- a/src/main/ai-vault/session-scanner-cursor-chat-meta.ts
+++ b/src/main/ai-vault/session-scanner-cursor-chat-meta.ts
@@ -1,5 +1,6 @@
 import { basename, dirname, join } from 'node:path'
 import { wslGatedReaddir, wslGatedStat } from '../native-chat/wsl-transcript-fs-access'
+import { WslTranscriptFsError } from '../native-chat/wsl-transcript-fs-gate'
 import { timestampIso } from './session-scanner-accumulator'
 import { extractString, normalizeTitleText, readJsonObjectIfExists } from './session-scanner-values'
 
@@ -86,7 +87,12 @@ async function readCursorChatMetaIndex(chatsRoot: string): Promise<Map<string, s
       .filter((entry) => entry.isDirectory())
       .map((entry) => entry.name)
       .sort()
-  } catch {
+  } catch (error) {
+    // Why: a refused WSL read is not "no chats"; letting it through keeps the
+    // session out of the parse cache instead of caching it without metadata.
+    if (error instanceof WslTranscriptFsError) {
+      throw error
+    }
     return new Map()
   }
   const signature = await readCursorChatsSignature(chatsRoot, workspaceDirs)
@@ -130,7 +136,10 @@ async function buildCursorChatMetaIndex(
     let chatDirs
     try {
       chatDirs = await wslGatedReaddir(join(chatsRoot, workspaceDir), 'scan')
-    } catch {
+    } catch (error) {
+      if (error instanceof WslTranscriptFsError) {
+        throw error
+      }
       continue
     }
     for (const chatDir of chatDirs) {
diff --git a/src/main/ai-vault/session-scanner-worker-client.ts b/src/main/ai-vault/session-scanner-worker-client.ts
index 93a0185383b..eae0c79dd9a 100644
--- a/src/main/ai-vault/session-scanner-worker-client.ts
+++ b/src/main/ai-vault/session-scanner-worker-client.ts
@@ -82,11 +82,13 @@ export class AiVaultScannerWorkerClient {
   }
 
   searchCoverage(
-    request: Pick<AiVaultServiceSearchRequest, 'roots'>
+    request: Pick<AiVaultServiceSearchRequest, 'roots'>,
+    signal?: AbortSignal
   ): Promise<AiVaultSearchCoverage> {
     return this.dispatch(
       { kind: 'searchCoverage', request },
-      TITLE_TIMEOUT_MS
+      TITLE_TIMEOUT_MS,
+      signal
     ) as Promise<AiVaultSearchCoverage>
   }
 
diff --git a/src/main/ai-vault/session-scanner-worker-spawn.ts b/src/main/ai-vault/session-scanner-worker-spawn.ts
index 255fed64f56..f8c38a654c5 100644
--- a/src/main/ai-vault/session-scanner-worker-spawn.ts
+++ b/src/main/ai-vault/session-scanner-worker-spawn.ts
@@ -66,9 +66,10 @@ export function searchAiVaultSessionsInWorker(
 }
 
 export function readAiVaultSearchCoverageInWorker(
-  request: Pick<AiVaultServiceSearchRequest, 'roots'>
+  request: Pick<AiVaultServiceSearchRequest, 'roots'>,
+  signal?: AbortSignal
 ): Promise<AiVaultSearchCoverage> {
-  return getSharedClient().searchCoverage(request)
+  return getSharedClient().searchCoverage(request, signal)
 }
 
 /** Null when no worker exists yet; the next one reads the new policy from its workerData. */
diff --git a/src/renderer/src/components/right-sidebar/AiVaultSearchSnippet.test.tsx b/src/renderer/src/components/right-sidebar/AiVaultSearchSnippet.test.tsx
index f2edba36071..c74966f7cc1 100644
--- a/src/renderer/src/components/right-sidebar/AiVaultSearchSnippet.test.tsx
+++ b/src/renderer/src/components/right-sidebar/AiVaultSearchSnippet.test.tsx
@@ -8,7 +8,7 @@ afterEach(cleanup)
 
 describe('aiVaultSearchSnippetSegments', () => {
   it('splits a snippet on its match markers', () => {
-    expect(aiVaultSearchSnippetSegments('fix the [strict] mode [bug]')).toEqual([
+    expect(aiVaultSearchSnippetSegments('fix the [[strict]] mode [[bug]]')).toEqual([
       { text: 'fix the ', matched: false },
       { text: 'strict', matched: true },
       { text: ' mode ', matched: false },
@@ -16,6 +16,14 @@ describe('aiVaultSearchSnippetSegments', () => {
     ])
   })
 
+  it('keeps literal brackets from a transcript as plain text', () => {
+    expect(aiVaultSearchSnippetSegments('read arr[0] then [[index]] it')).toEqual([
+      { text: 'read arr[0] then ', matched: false },
+      { text: 'index', matched: true },
+      { text: ' it', matched: false }
+    ])
+  })
+
   it('leaves an unmarked snippet as one plain segment', () => {
     expect(aiVaultSearchSnippetSegments('no markers here')).toEqual([
       { text: 'no markers here', matched: false }
@@ -27,7 +35,7 @@ describe('AiVaultSearchEvidenceLine', () => {
   it('renders the role and marks the matched terms', () => {
     render(
       <AiVaultSearchEvidenceLine
-        evidence={{ role: 'user', timestamp: null, snippet: 'fix the [strict] mode' }}
+        evidence={{ role: 'user', timestamp: null, snippet: 'fix the [[strict]] mode' }}
       />
     )
     expect(screen.getByText('You')).toBeTruthy()
diff --git a/src/renderer/src/components/right-sidebar/AiVaultSearchSnippet.tsx b/src/renderer/src/components/right-sidebar/AiVaultSearchSnippet.tsx
index 5a842416f12..a37a3badb57 100644
--- a/src/renderer/src/components/right-sidebar/AiVaultSearchSnippet.tsx
+++ b/src/renderer/src/components/right-sidebar/AiVaultSearchSnippet.tsx
@@ -12,11 +12,11 @@ const ROLE_GLYPH = {
 
 export type AiVaultSearchSnippetSegment = { text: string; matched: boolean }
 
-/** Splits an FTS5 snippet on its `[term]` match markers. */
+/** Splits an FTS5 snippet on its `[[term]]` match markers; single brackets are text. */
 export function aiVaultSearchSnippetSegments(snippet: string): AiVaultSearchSnippetSegment[] {
   const segments: AiVaultSearchSnippetSegment[] = []
   let cursor = 0
-  const pattern = /\[([^[\]]*)\]/g
+  const pattern = /\[\[(.*?)\]\]/g
   let match: RegExpExecArray | null
   while ((match = pattern.exec(snippet)) !== null) {
     if (match.index > cursor) {
diff --git a/src/renderer/src/components/right-sidebar/AiVaultSessionRow.tsx b/src/renderer/src/components/right-sidebar/AiVaultSessionRow.tsx
index dae24db17d4..a518f626030 100644
--- a/src/renderer/src/components/right-sidebar/AiVaultSessionRow.tsx
+++ b/src/renderer/src/components/right-sidebar/AiVaultSessionRow.tsx
@@ -188,7 +188,7 @@ export function VaultSessionRow({
               onRequestDelete={requestDelete}
             />
           </div>
-          {!detailsExpanded && (latestTurn || !searchEvidence) ? (
+          {!detailsExpanded && !searchEvidence ? (
             <div className="mt-0.5 min-w-0 line-clamp-2 text-[12px] leading-4 text-muted-foreground">
               {latestTurn ? (
                 <>
diff --git a/src/renderer/src/components/right-sidebar/ai-vault-search-coverage-poll.test.ts b/src/renderer/src/components/right-sidebar/ai-vault-search-coverage-poll.test.ts
index 968eb0169af..ea342711cac 100644
--- a/src/renderer/src/components/right-sidebar/ai-vault-search-coverage-poll.test.ts
+++ b/src/renderer/src/components/right-sidebar/ai-vault-search-coverage-poll.test.ts
@@ -59,6 +59,27 @@ describe('useAiVaultSearchCoveragePoll', () => {
     expect(searchCoverage).toHaveBeenCalledTimes(callsAfterFirstRead)
   })
 
+  it('ignores a slow running answer that lands after a newer complete one', async () => {
+    let releaseFirst: (value: ReturnType<typeof coverage>) => void = () => undefined
+    searchCoverage
+      .mockImplementationOnce(
+        () =>
+          new Promise((resolve) => {
+            releaseFirst = resolve
+          })
+      )
+      .mockResolvedValueOnce(coverage('complete'))
+    const { result } = renderHook(() => useAiVaultSearchCoveragePoll(true), { wrapper })
+    await act(async () => {
+      await vi.advanceTimersByTimeAsync(AI_VAULT_SEARCH_COVERAGE_POLL_MS)
+    })
+    expect(result.current?.backfill).toBe('complete')
+    await act(async () => {
+      releaseFirst(coverage('running'))
+    })
+    expect(result.current?.backfill).toBe('complete')
+  })
+
   it('keeps polling while the backfill is still running', async () => {
     searchCoverage.mockResolvedValue(coverage('running'))
     renderHook(() => useAiVaultSearchCoveragePoll(true), { wrapper })
diff --git a/src/renderer/src/components/right-sidebar/ai-vault-search-coverage-poll.ts b/src/renderer/src/components/right-sidebar/ai-vault-search-coverage-poll.ts
index 0ed4cc3ab3c..cace2f2bae4 100644
--- a/src/renderer/src/components/right-sidebar/ai-vault-search-coverage-poll.ts
+++ b/src/renderer/src/components/right-sidebar/ai-vault-search-coverage-poll.ts
@@ -20,16 +20,20 @@ export function useAiVaultSearchCoveragePoll(enabled: boolean): AiVaultSearchCov
       return
     }
     let stopped = false
+    let generation = 0
     // One interval, cleared unconditionally on unmount; the reads it drives stop
     // once the backfill is complete because there is nothing left to watch.
     const interval = setInterval(() => {
       read()
     }, AI_VAULT_SEARCH_COVERAGE_POLL_MS)
     function read(): void {
+      generation += 1
+      const issued = generation
       void window.api.aiVault
         .searchCoverage()
         .then((next) => {
-          if (stopped) {
+          // Why: a slow 'running' answer must not land after a newer 'complete'.
+          if (stopped || issued !== generation) {
             return
           }
           setCoverage(next)
diff --git a/src/renderer/src/components/right-sidebar/ai-vault-session-search-request.ts b/src/renderer/src/components/right-sidebar/ai-vault-session-search-request.ts
index cfdd27733fd..2f5caa2c258 100644
--- a/src/renderer/src/components/right-sidebar/ai-vault-session-search-request.ts
+++ b/src/renderer/src/components/right-sidebar/ai-vault-session-search-request.ts
@@ -46,11 +46,8 @@ export function useAiVaultSessionSearchRequest(
   // Serialized so a fresh object identity with identical values does not
   // restart the debounce on every parent render.
   const argsKey = args ? JSON.stringify(args) : ''
-  const argsKeyRef = useRef(argsKey)
-  argsKeyRef.current = argsKey
 
-  const issue = useCallback((overrides: Partial<AiVaultSearchArgs>): void => {
-    const key = argsKeyRef.current
+  const issue = useCallback((key: string, overrides: Partial<AiVaultSearchArgs>): void => {
     if (!key) {
       return
     }
@@ -75,27 +72,44 @@ export function useAiVaultSessionSearchRequest(
       })
   }, [])
 
+  // Why: a flush has to cancel the debounce the args effect armed, and the two
+  // effects cannot share locals, so the args effect publishes its cancel.
+  const cancelDebounceRef = useRef<() => void>(() => undefined)
+
   useEffect(() => {
     if (!argsKey) {
       return
     }
     const typingTimer = setTimeout(
-      () => issue({ tier: 'conversation', refresh: false }),
+      () => issue(argsKey, { tier: 'conversation', refresh: false }),
       AI_VAULT_SEARCH_TYPING_DELAY_MS
     )
-    const settledTimer = setTimeout(() => issue({ tier: 'full' }), AI_VAULT_SEARCH_SETTLED_DELAY_MS)
-    return () => {
+    const settledTimer = setTimeout(
+      () => issue(argsKey, { tier: 'full' }),
+      AI_VAULT_SEARCH_SETTLED_DELAY_MS
+    )
+    const cancel = (): void => {
       clearTimeout(typingTimer)
       clearTimeout(settledTimer)
+    }
+    cancelDebounceRef.current = cancel
+    return () => {
+      cancel()
+      cancelDebounceRef.current = () => undefined
       // Retires anything still in flight for the query being replaced.
       sequenceRef.current += 1
     }
   }, [argsKey, issue])
 
+  // Why: the args effect must not re-run on flush (it would restart the
+  // debounce), so the flush reads the key it was rendered with. The pending
+  // debounce is dropped so a late typing-tier request cannot outrank it.
   useEffect(() => {
     if (flushSignal > 0) {
-      issue({ tier: 'full' })
+      cancelDebounceRef.current()
+      issue(argsKey, { tier: 'full' })
     }
+    // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [flushSignal, issue])
 
   const current = settled?.key === argsKey ? settled : null
diff --git a/src/renderer/src/components/right-sidebar/ai-vault-session-search-results.ts b/src/renderer/src/components/right-sidebar/ai-vault-session-search-results.ts
index 55681816289..2be9febfd33 100644
--- a/src/renderer/src/components/right-sidebar/ai-vault-session-search-results.ts
+++ b/src/renderer/src/components/right-sidebar/ai-vault-session-search-results.ts
@@ -103,8 +103,8 @@ export function useAiVaultSessionSearchResults(input: {
         key: 'ai-vault-search-results',
         label: translate(
           'auto.components.right.sidebar.AiVaultPanel.searchMatches',
-          '{{value0}} matches',
-          { value0: hitSessions.sessions.length }
+          '{{count}} matches',
+          { count: hitSessions.sessions.length }
         ),
         sessions: hitSessions.sessions
       }
@@ -117,7 +117,12 @@ export function useAiVaultSessionSearchResults(input: {
       loading,
       updating,
       error,
-      coverage: result?.coverage ?? polledCoverage,
+      // Why: the poll keeps going after a retained result, so it is the fresher
+      // read once it says the backfill is done.
+      coverage:
+        polledCoverage?.backfill === 'complete'
+          ? polledCoverage
+          : (result?.coverage ?? polledCoverage),
       disabled: isAiVaultSearchDisabled(result?.coverage),
       flush,
       groups,
diff --git a/src/renderer/src/i18n/en-runtime-required.json b/src/renderer/src/i18n/en-runtime-required.json
index af43a08f37a..eef19487c1d 100644
--- a/src/renderer/src/i18n/en-runtime-required.json
+++ b/src/renderer/src/i18n/en-runtime-required.json
@@ -687,7 +687,9 @@
             "localSessionSshWorkspaceUnsupported": "This session's history is stored on this machine, so it can't resume in an SSH workspace. Open a local workspace instead.",
             "localWorkspacesOnly": "Resume from history is only available in local workspaces.",
             "remoteBrowseLocalHistory": "Remote workspaces can browse local history. Resume actions run from local workspaces.",
-            "valueCopyFailed": "Unable to copy {{value0}}"
+            "valueCopyFailed": "Unable to copy {{value0}}",
+            "searchMatches_one": "{{count}} match",
+            "searchMatches_other": "{{count}} matches"
           },
           "AiVaultPanelControls": {
             "allSessions": "All sessions",
diff --git a/src/renderer/src/i18n/locales/en.json b/src/renderer/src/i18n/locales/en.json
index 7eecb464aa7..e30c3151648 100644
--- a/src/renderer/src/i18n/locales/en.json
+++ b/src/renderer/src/i18n/locales/en.json
@@ -13025,7 +13025,9 @@
             "prepareSessionResumeFailed": "Could not prepare this session for resume.",
             "sessionDeleted": "Session deleted",
             "sessionDeleteFailed": "Couldn't delete the session",
-            "searchMatches": "{{value0}} matches"
+            "searchMatches_one": "{{count}} match",
+            "searchMatches_other": "{{count}} matches",
+            "searchMatches": "{{count}} matches"
           },
           "AiVaultPanelControls": {
             "scanningSessions": "Scanning sessions",
diff --git a/src/shared/ai-vault-search-settings.ts b/src/shared/ai-vault-search-settings.ts
index 9648791df80..8ee17f97dd2 100644
--- a/src/shared/ai-vault-search-settings.ts
+++ b/src/shared/ai-vault-search-settings.ts
@@ -25,7 +25,10 @@ export function normalizeAiVaultSearchHistoryDays(value: unknown): number | null
   if (typeof value !== 'number' || !Number.isFinite(value) || value <= 0) {
     return null
   }
-  return Math.min(HISTORY_DAYS_MAX, Math.floor(value))
+  const days = Math.floor(value)
+  // Why: a fractional day floors to 0, which the UI shows as "all history"
+  // while the cutoff would be "now"; make the two agree.
+  return days <= 0 ? null : Math.min(HISTORY_DAYS_MAX, days)
 }
 
 export function resolveAiVaultSearchSettings(
diff --git a/src/shared/ai-vault-search-types.ts b/src/shared/ai-vault-search-types.ts
index e6d8db63d9f..56ffda16616 100644
--- a/src/shared/ai-vault-search-types.ts
+++ b/src/shared/ai-vault-search-types.ts
@@ -24,7 +24,7 @@ export type AiVaultSearchArgs = {
 export type AiVaultSearchEvidence = {
   role: AiVaultSessionPreviewMessage['role']
   timestamp: string | null
-  /** FTS5 snippet with the matched terms wrapped in `[` `]`. */
+  /** FTS5 snippet with the matched terms wrapped in `[[` `]]`. */
   snippet: string
 }
 
@@ -84,3 +84,7 @@ export type AiVaultSearchCoverage = {
   filesPending: number
   lastIndexedAt: string | null
 }
+
+/** Snippet match markers; doubled so literal brackets in code never read as a match. */
+export const AI_VAULT_SEARCH_SNIPPET_MARK_OPEN = '[['
+export const AI_VAULT_SEARCH_SNIPPET_MARK_CLOSE = ']]'