@@ -25,6 +25,9 @@ npm-app/src/__tests__/data/
 debug/
 .context/
 docs/bot-detection.md
+# Issue-specific plans/specs belong in Linear, not the repository. Existing
+# tracked historical specs remain tracked; this keeps new local artifacts out.
+docs/specs/
 .codex
 
 # Nx cache directories
 
@@ -8,6 +8,7 @@ import {
   ADS_FIRST_PARTY_SETTLEMENT_EVENT,
   ADS_FIRST_PARTY_VIEW_ACK_EVENT,
   ADS_EXTERNAL_CONVERSION_POSTBACK_EVENT,
+  ADS_IMPREZIA_FETCH_COMPLETED_EVENT,
   CONTEXT_PRUNING_COMPLETED_EVENT,
   getAxiomOnlyLogEvent,
   STREAM_RECOVERY_EVENT,
@@ -272,6 +273,71 @@ describe('getAxiomOnlyLogEvent', () => {
     })
   })
 
+  test('keeps Imprezia completion telemetry bounded and identity-free', () => {
+    expect(
+      getAxiomOnlyLogEvent({
+        axiomEvent: ADS_IMPREZIA_FETCH_COMPLETED_EVENT,
+        outcome: 'provider_error',
+        selection_reason: 'fallback',
+        experiment_arm: 'control',
+        surface: 'freebuff_web_chat',
+        ad_count: 0,
+        duration_ms: 42,
+        test_mode: false,
+        failure_class: 'provider_failure',
+        userId: 'user-private',
+        sessionId: 'session-private',
+        requestId: 'request-private',
+        request: 'private prompt',
+        response: 'private response',
+        ad: { title: 'private creative' },
+        clickUrl: 'https://private.example/click',
+        error: new Error('private raw provider error'),
+      }),
+    ).toEqual({
+      event: ADS_IMPREZIA_FETCH_COMPLETED_EVENT,
+      data: {
+        outcome: 'provider_error',
+        selection_reason: 'fallback',
+        experiment_arm: 'control',
+        surface: 'freebuff_web_chat',
+        ad_count: 0,
+        duration_ms: 42,
+        test_mode: false,
+        failure_class: 'provider_failure',
+      },
+    })
+  })
+
+  test('rejects unbounded or incomplete Imprezia completion dimensions', () => {
+    const valid = {
+      axiomEvent: ADS_IMPREZIA_FETCH_COMPLETED_EVENT,
+      outcome: 'no_fill',
+      selection_reason: 'primary',
+      experiment_arm: 'imprezia_first',
+      surface: 'freebuff_web_chat',
+      ad_count: 0,
+      duration_ms: 42,
+      test_mode: false,
+    }
+    for (const invalid of [
+      { ...valid, outcome: 'private raw error' },
+      { ...valid, selection_reason: 'campaign-123' },
+      { ...valid, experiment_arm: 'user-123' },
+      { ...valid, surface: 'https://private.example' },
+      { ...valid, ad_count: 2 },
+      { ...valid, outcome: 'fill', ad_count: 0 },
+      { ...valid, duration_ms: -1 },
+      { ...valid, duration_ms: 60_001 },
+      { ...valid, failure_class: 'raw upstream stack trace' },
+      { ...valid, test_mode: 'false' },
+      // Every dimension except failure_class is required.
+      { ...valid, experiment_arm: undefined },
+    ]) {
+      expect(getAxiomOnlyLogEvent(invalid)).toBeNull()
+    }
+  })
+
   test('names and sanitizes first-party selection telemetry', () => {
     expect(
       getAxiomOnlyLogEvent({
 
@@ -50,6 +50,11 @@ export const ADS_FIRST_PARTY_IMPRESSION_RECORDED_EVENT =
  * opaque click/event identifiers never leave the request handler. */
 export const ADS_EXTERNAL_CONVERSION_POSTBACK_EVENT =
   'ads.external_conversion_postback' as const
+/** Browser-side Imprezia decisions. The route deliberately reports only
+ * bounded serving dimensions: request/content/creative identifiers, URLs, and
+ * raw provider errors never enter this event. */
+export const ADS_IMPREZIA_FETCH_COMPLETED_EVENT =
+  'ads.imprezia_fetch_completed' as const
 
 type AxiomOnlyFieldType = 'string' | 'number' | 'boolean'
 type AxiomOnlyFieldSchema = Record<string, AxiomOnlyFieldType>
@@ -164,6 +169,90 @@ const ADS_FETCH_COMPLETED_FIELDS = {
   yield_live_evidence_status: 'string',
 } as const satisfies AxiomOnlyFieldSchema
 
+const ADS_IMPREZIA_FETCH_COMPLETED_FIELDS = {
+  outcome: 'string',
+  selection_reason: 'string',
+  experiment_arm: 'string',
+  surface: 'string',
+  ad_count: 'number',
+  duration_ms: 'number',
+  test_mode: 'boolean',
+  failure_class: 'string',
+} as const satisfies AxiomOnlyFieldSchema
+
+const ADS_IMPREZIA_FETCH_OUTCOMES = [
+  'fill',
+  'no_fill',
+  'timeout',
+  'provider_error',
+  'not_configured',
+  'not_eligible',
+] as const
+const ADS_IMPREZIA_SELECTION_REASONS = ['primary', 'fallback'] as const
+const ADS_IMPREZIA_EXPERIMENT_ARMS = [
+  'imprezia_forced',
+  'imprezia_first',
+  'control',
+] as const
+const ADS_IMPREZIA_BROWSER_SURFACES = [
+  'freebuff_web_chat',
+  'chat_assistant',
+] as const
+const ADS_IMPREZIA_FAILURE_CLASSES = [
+  'missing_api_key',
+  'missing_user_agent',
+  'invalid_source_url',
+  'provider_timeout',
+  'provider_failure',
+  'client_exception',
+] as const
+const ADS_IMPREZIA_MAX_DURATION_MS = 60_000
+
+function sanitizeImpreziaFetchCompletedFields(
+  record: Record<string, unknown>,
+): AxiomOnlyLogEvent['data'] | null {
+  const data = sanitizeAllowlistedFields(
+    record,
+    ADS_IMPREZIA_FETCH_COMPLETED_FIELDS,
+  )
+  const outcome = data.outcome
+  const selectionReason = data.selection_reason
+  const experimentArm = data.experiment_arm
+  const surface = data.surface
+  const adCount = data.ad_count
+  const durationMs = data.duration_ms
+  const testMode = data.test_mode
+  const failureClass = data.failure_class
+
+  if (
+    !ADS_IMPREZIA_FETCH_OUTCOMES.includes(
+      outcome as (typeof ADS_IMPREZIA_FETCH_OUTCOMES)[number],
+    ) ||
+    !ADS_IMPREZIA_SELECTION_REASONS.includes(
+      selectionReason as (typeof ADS_IMPREZIA_SELECTION_REASONS)[number],
+    ) ||
+    !ADS_IMPREZIA_EXPERIMENT_ARMS.includes(
+      experimentArm as (typeof ADS_IMPREZIA_EXPERIMENT_ARMS)[number],
+    ) ||
+    !ADS_IMPREZIA_BROWSER_SURFACES.includes(
+      surface as (typeof ADS_IMPREZIA_BROWSER_SURFACES)[number],
+    ) ||
+    (adCount !== 0 && adCount !== 1) ||
+    (outcome === 'fill' ? adCount !== 1 : adCount !== 0) ||
+    typeof durationMs !== 'number' ||
+    durationMs < 0 ||
+    durationMs > ADS_IMPREZIA_MAX_DURATION_MS ||
+    typeof testMode !== 'boolean' ||
+    (failureClass !== undefined &&
+      !ADS_IMPREZIA_FAILURE_CLASSES.includes(
+        failureClass as (typeof ADS_IMPREZIA_FAILURE_CLASSES)[number],
+      ))
+  ) {
+    return null
+  }
+  return data
+}
+
 /**
  * First-party inventory selection is operational telemetry only. In
  * particular, campaign/creative/placement arrays and user/session IDs stay
@@ -314,6 +403,7 @@ export type AxiomOnlyLogEvent = {
     | typeof ADS_FIRST_PARTY_CLICK_RECORDED_EVENT
     | typeof ADS_FIRST_PARTY_IMPRESSION_RECORDED_EVENT
     | typeof ADS_EXTERNAL_CONVERSION_POSTBACK_EVENT
+    | typeof ADS_IMPREZIA_FETCH_COMPLETED_EVENT
   data: Record<string, string | number | boolean>
 }
 
@@ -378,6 +468,10 @@ export function getAxiomOnlyLogEvent(
       data: sanitizeAllowlistedFields(record, ADS_FETCH_COMPLETED_FIELDS),
     }
   }
+  if (eventName === ADS_IMPREZIA_FETCH_COMPLETED_EVENT) {
+    const data = sanitizeImpreziaFetchCompletedFields(record)
+    return data ? { event: eventName, data } : null
+  }
   if (eventName === ADS_FIRST_PARTY_DECISION_EVENT) {
     return {
       event: eventName,