Clarify AI cost estimates with pricing coverage

frontend-modern/src/components/AI/AICostDashboard.tsx

@@ -65,6 +65,12 @@ export const AICostDashboard: Component = () => {
     return data.provider_models.some((pm) => pm.pricing_known);
   });
 
+  const unpricedProviderModels = createMemo(() => {
+    const data = summary();
+    if (!data) return [];
+    return (data.provider_models ?? []).filter((pm) => !pm.pricing_known && (pm.total_tokens ?? 0) > 0);
+  });
+
   const estimatedTotalUSD = createMemo(() => {
     const data = summary();
     if (!data || !anyPricingKnown()) return null;
@@ -412,6 +418,25 @@ export const AICostDashboard: Component = () => {
 
               <div class="text-xs text-gray-500 dark:text-gray-400">
                 USD is an estimate based on public list prices. It may differ from billing.
+                <Show when={unpricedProviderModels().length > 0}>
+                  <span class="ml-2">
+                    Estimated spend is partial. Pricing is unknown for{' '}
+                    {unpricedProviderModels()
+                      .slice(0, 6)
+                      .map(
+                        (pm) =>
+                          `${PROVIDER_NAMES[pm.provider as keyof typeof PROVIDER_NAMES] || pm.provider}/${pm.model}`,
+                      )
+                      .join(', ')}
+                    <Show when={unpricedProviderModels().length > 6}>
+                      <span> (+{unpricedProviderModels().length - 6} more)</span>
+                    </Show>
+                    .
+                  </span>
+                </Show>
+                <Show when={summary()?.pricing_as_of}>
+                  <span class="ml-2">Prices as of {summary()?.pricing_as_of}.</span>
+                </Show>
               </div>
 
               <div class="flex items-center justify-between gap-3">

frontend-modern/src/types/ai.ts

@@ -220,6 +220,7 @@ export interface AICostSummary {
   retention_days: number;
   effective_days: number;
   truncated: boolean;
+  pricing_as_of?: string;
   provider_models: AICostProviderModelSummary[];
   use_cases: AICostUseCaseSummary[];
   targets: AICostTargetSummary[];

internal/ai/cost/pricing.go

@@ -31,6 +31,11 @@ type modelPrice struct {
 
 const pricingAsOf = "2025-12"
 
+// PricingAsOf indicates the effective date of the pricing table used for estimation.
+func PricingAsOf() string {
+	return pricingAsOf
+}
+
 // NOTE: Keep this table small and conservative.
 // The goal is quick estimation and relative comparisons, not exact billing.
 var providerPrices = map[string][]modelPrice{

internal/ai/cost/store.go

@@ -237,6 +237,7 @@ func (s *Store) GetSummary(days int) Summary {
 		RetentionDays:  retentionDays,
 		EffectiveDays:  effectiveDays,
 		Truncated:      truncated,
+		PricingAsOf:    PricingAsOf(),
 		ProviderModels: providerModels,
 		UseCases:       summarizeUseCases(events),
 		Targets:        summarizeTargets(events),
@@ -356,6 +357,8 @@ type Summary struct {
 	EffectiveDays int  `json:"effective_days"`
 	Truncated     bool `json:"truncated"`
 
+	PricingAsOf string `json:"pricing_as_of,omitempty"`
+
 	ProviderModels []ProviderModelSummary `json:"provider_models"`
 	UseCases       []UseCaseSummary       `json:"use_cases"`
 	Targets        []TargetSummary        `json:"targets"`

internal/ai/service.go

@@ -138,6 +138,7 @@ func (s *Service) GetCostSummary(days int) cost.Summary {
 			RetentionDays:  cost.DefaultMaxDays,
 			EffectiveDays:  effectiveDays,
 			Truncated:      truncated,
+			PricingAsOf:    cost.PricingAsOf(),
 			ProviderModels: []cost.ProviderModelSummary{},
 			UseCases:       []cost.UseCaseSummary{},
 			DailyTotals:    []cost.DailySummary{},

internal/api/ai_handlers.go

@@ -2441,6 +2441,7 @@ func (h *AISettingsHandler) HandleGetAICostSummary(w http.ResponseWriter, r *htt
 	} else {
 		summary = cost.Summary{
 			Days:           days,
+			PricingAsOf:    cost.PricingAsOf(),
 			ProviderModels: []cost.ProviderModelSummary{},
 			DailyTotals:    []cost.DailySummary{},
 			Totals:         cost.ProviderModelSummary{Provider: "all"},