feat(ai-gateway): support fallback exclusive pricing

apps/web/src/lib/ai-gateway/models.test.ts

@@ -122,7 +122,7 @@ describe('isFreeModel', () => {
       expect(gpt_5_6_sol_stealth_model.internal_id).toBe('openai/gpt-5.6-sol:optimized');
       expect(gpt_5_6_sol_stealth_model.gateway).toBe('martian');
       expect(getInferenceProvider(gpt_5_6_sol_stealth_model)?.slug).toBe('stealth');
-      expect(gpt_5_6_sol_stealth_model.pricing).toEqual([
+      expect(gpt_5_6_sol_stealth_model.pricing?.tiers).toEqual([
         {
           start_context_length: 0,
           pricing: {
@@ -147,9 +147,9 @@ describe('isFreeModel', () => {
     test('all Kilo exclusive models should have either no pricing or valid ordered pricing tiers', () => {
       for (const model of kiloExclusiveModels) {
         if (model.pricing) {
-          expect(model.pricing[0].start_context_length).toBe(0);
+          expect(model.pricing.tiers[0].start_context_length).toBe(0);
           let previousStartContextLength = -1;
-          for (const tier of model.pricing) {
+          for (const tier of model.pricing.tiers) {
             expect(typeof tier.pricing.prompt_per_million).toBe('number');
             expect(typeof tier.pricing.completion_per_million).toBe('number');
             expect(tier.start_context_length).toBeGreaterThan(previousStartContextLength);

apps/web/src/lib/ai-gateway/processUsage.calculateKiloExclusiveCost.test.ts

@@ -13,11 +13,19 @@ const makeUsage = (overrides: Partial<JustTheCostsUsageStats> = {}): JustTheCost
   ...overrides,
 });
 
+const fallbackOnlyModel = {
+  ...claude_opus_4_7_stealth_model,
+  pricing: claude_opus_4_7_stealth_model.pricing && {
+    ...claude_opus_4_7_stealth_model.pricing,
+    fallbackOnly: true,
+  },
+};
+
 describe('calculateKiloExclusiveCost_mUsd with stealth Claude Opus 4.7', () => {
   test('uses the 20% lower flat price for uncached tokens', () => {
     const result = calculateKiloExclusiveCost_mUsd(
       claude_opus_4_7_stealth_model,
-      makeUsage({ inputTokens: 100_000, outputTokens: 10_000 })
+      makeUsage({ inputTokens: 100_000, outputTokens: 10_000, cost_mUsd: 999_000 })
     );
     expect(result).toBe(600_000);
   });
@@ -34,4 +42,20 @@ describe('calculateKiloExclusiveCost_mUsd with stealth Claude Opus 4.7', () => {
     );
     expect(result).toBe(735_000);
   });
+
+  test('uses fallback-only pricing when market cost is missing', () => {
+    const result = calculateKiloExclusiveCost_mUsd(
+      fallbackOnlyModel,
+      makeUsage({ inputTokens: 100_000, outputTokens: 10_000 })
+    );
+    expect(result).toBe(600_000);
+  });
+
+  test('preserves reported market cost with fallback-only pricing', () => {
+    const result = calculateKiloExclusiveCost_mUsd(
+      fallbackOnlyModel,
+      makeUsage({ inputTokens: 100_000, outputTokens: 10_000, cost_mUsd: 123_000 })
+    );
+    expect(result).toBeUndefined();
+  });
 });

apps/web/src/lib/ai-gateway/processUsage.ts

@@ -1188,11 +1188,14 @@ export function parseMicrodollarUsageFromString(
 export function calculateKiloExclusiveCost_mUsd(
   model: KiloExclusiveModel,
   usage: JustTheCostsUsageStats
-): number {
+): number | undefined {
   const pricing = model?.pricing;
   if (!pricing) {
     return 0;
   }
+  if (pricing.fallbackOnly && usage.cost_mUsd > 0) {
+    return undefined;
+  }
   const uncachedInputTokens = usage.inputTokens - usage.cacheHitTokens - usage.cacheWriteTokens;
   if (uncachedInputTokens < 0) {
     captureMessage('SUSPICIOUS: negative uncached input tokens', {
@@ -1209,7 +1212,7 @@ export function calculateKiloExclusiveCost_mUsd(
         cacheHitTokens: usage.cacheHitTokens,
         cacheWriteTokens: usage.cacheWriteTokens,
       },
-      pricing
+      pricing.tiers
     )
   );
 }
@@ -1288,8 +1291,11 @@ export async function processTokenData(
 
   const kiloExclusiveModel = findKiloExclusiveModel(usageContext.requested_model);
   if (kiloExclusiveModel?.pricing) {
-    usageStats.market_cost = usageStats.cost_mUsd;
-    usageStats.cost_mUsd = calculateKiloExclusiveCost_mUsd(kiloExclusiveModel, usageStats);
+    const exclusiveCost_mUsd = calculateKiloExclusiveCost_mUsd(kiloExclusiveModel, usageStats);
+    if (exclusiveCost_mUsd !== undefined) {
+      usageStats.market_cost = usageStats.cost_mUsd;
+      usageStats.cost_mUsd = exclusiveCost_mUsd;
+    }
   }
 
   const customCost_mUsd = calculateCustomCost_mUsd(usageContext.requested_model, usageStats);

apps/web/src/lib/ai-gateway/providers/anthropic.constants.ts

@@ -41,7 +41,7 @@ export const claude_opus_4_8_stealth_model: KiloExclusiveModel = {
   max_completion_tokens: 128_000,
   gateway: 'martian',
   flags: ['reasoning', 'vision', 'stealth', 'requires-data-collection'],
-  pricing: CLAUDE_OPUS_STEALTH_PRICING,
+  pricing: { tiers: CLAUDE_OPUS_STEALTH_PRICING },
   inference_provider_restriction: [],
 };
 
@@ -56,7 +56,7 @@ export const claude_opus_4_7_stealth_model: KiloExclusiveModel = {
   max_completion_tokens: 128_000,
   gateway: 'martian',
   flags: ['reasoning', 'vision', 'stealth', 'requires-data-collection'],
-  pricing: CLAUDE_OPUS_STEALTH_PRICING,
+  pricing: { tiers: CLAUDE_OPUS_STEALTH_PRICING },
   inference_provider_restriction: [],
 };
 
@@ -83,7 +83,7 @@ export const claude_sonnet_4_6_stealth_model: KiloExclusiveModel = {
   max_completion_tokens: 64_000,
   gateway: 'martian',
   flags: ['reasoning', 'vision', 'stealth', 'requires-data-collection'],
-  pricing: CLAUDE_SONNET_STEALTH_PRICING,
+  pricing: { tiers: CLAUDE_SONNET_STEALTH_PRICING },
   inference_provider_restriction: [],
 };
 
@@ -98,7 +98,7 @@ export const claude_opus_4_6_stealth_model: KiloExclusiveModel = {
   max_completion_tokens: 128_000,
   gateway: 'martian',
   flags: ['reasoning', 'vision', 'stealth', 'requires-data-collection'],
-  pricing: CLAUDE_OPUS_STEALTH_PRICING,
+  pricing: { tiers: CLAUDE_OPUS_STEALTH_PRICING },
   inference_provider_restriction: [],
 };
 

apps/web/src/lib/ai-gateway/providers/deepseek.ts

@@ -15,17 +15,19 @@ export const deepseek_v4_pro_discounted_model: KiloExclusiveModel = {
   max_completion_tokens: 384000,
   gateway: 'openrouter',
   flags: ['reasoning', 'requires-data-collection', 'vercel-routing'],
-  pricing: [
-    {
-      start_context_length: 0,
-      pricing: {
-        prompt_per_million: 0.435,
-        completion_per_million: 0.87,
-        input_cache_read_per_million: 0.003625,
-        input_cache_write_per_million: null,
+  pricing: {
+    tiers: [
+      {
+        start_context_length: 0,
+        pricing: {
+          prompt_per_million: 0.435,
+          completion_per_million: 0.87,
+          input_cache_read_per_million: 0.003625,
+          input_cache_write_per_million: null,
+        },
       },
-    },
-  ],
+    ],
+  },
   inference_provider_restriction: ['deepseek'],
 };
 
@@ -40,17 +42,19 @@ const deepseek_v4_flash_discounted_model: KiloExclusiveModel = {
   max_completion_tokens: 384000,
   gateway: 'openrouter',
   flags: ['reasoning', 'requires-data-collection', 'vercel-routing'],
-  pricing: [
-    {
-      start_context_length: 0,
-      pricing: {
-        prompt_per_million: 0.14,
-        completion_per_million: 0.28,
-        input_cache_read_per_million: 0.0028,
-        input_cache_write_per_million: null,
+  pricing: {
+    tiers: [
+      {
+        start_context_length: 0,
+        pricing: {
+          prompt_per_million: 0.14,
+          completion_per_million: 0.28,
+          input_cache_read_per_million: 0.0028,
+          input_cache_write_per_million: null,
+        },
       },
-    },
-  ],
+    ],
+  },
   inference_provider_restriction: ['deepseek'],
 };
 

apps/web/src/lib/ai-gateway/providers/kilo-exclusive-model.test.ts

@@ -93,10 +93,24 @@ describe('convertFromKiloExclusiveModel', () => {
   it('only exposes the cheapest pricing tier in model metadata', () => {
     const model = makeModel({
       internal_id: 'vendor/x',
-      pricing: [
-        { start_context_length: 0, pricing: pricing(1) },
-        { start_context_length: 100, pricing: pricing(2) },
-      ],
+      pricing: {
+        tiers: [
+          { start_context_length: 0, pricing: pricing(1) },
+          { start_context_length: 100, pricing: pricing(2) },
+        ],
+      },
+    });
+
+    expect(convertFromKiloExclusiveModel(model).pricing.prompt).toBe('0.000001000000');
+  });
+
+  it('exposes fallback-only pricing in model metadata', () => {
+    const model = makeModel({
+      internal_id: 'vendor/x',
+      pricing: {
+        fallbackOnly: true,
+        tiers: [{ start_context_length: 0, pricing: pricing(1) }],
+      },
     });
 
     expect(convertFromKiloExclusiveModel(model).pricing.prompt).toBe('0.000001000000');

apps/web/src/lib/ai-gateway/providers/kilo-exclusive-model.ts

@@ -37,6 +37,12 @@ export type PricingTier = {
 
 export type PricingTiers = readonly [PricingTier, ...PricingTier[]];
 
+export type KiloExclusivePricing = {
+  tiers: PricingTiers;
+  /** Only use these tiers when the upstream response does not report a positive market cost. */
+  fallbackOnly?: boolean;
+};
+
 export function calculateCost_mUsd(usage: Usage, pricingTiers: PricingTiers): number {
   if (pricingTiers[0].start_context_length !== 0) {
     throw new Error('The first pricing tier must start at context length 0');
@@ -75,7 +81,7 @@ export type KiloExclusiveModel = {
   flags: KiloExclusiveModelFlag[];
   gateway: ProviderId;
   internal_id: string;
-  pricing: PricingTiers | null;
+  pricing: KiloExclusivePricing | null;
   /**
    * Upstream inference providers this model may be routed to; empty means no
    * restriction. Only honored by the OpenRouter and Vercel AI Gateway upstreams.
@@ -207,7 +213,7 @@ function formatPricePerMillionAsPerToken(price: number | null | undefined): stri
 }
 
 export function convertFromKiloExclusiveModel(model: KiloExclusiveModel) {
-  const cheapestPricing = model.pricing?.[0].pricing;
+  const cheapestPricing = model.pricing?.tiers[0].pricing;
   const isFree = !model.pricing;
   return {
     id: model.public_id,

apps/web/src/lib/ai-gateway/providers/openai-exclusive.ts

@@ -11,25 +11,27 @@ export const gpt_5_6_sol_stealth_model: KiloExclusiveModel = {
   max_completion_tokens: 128_000,
   gateway: 'martian',
   flags: ['reasoning', 'vision', 'stealth', 'requires-data-collection'],
-  pricing: [
-    {
-      start_context_length: 0,
-      pricing: {
-        prompt_per_million: 4,
-        completion_per_million: 24,
-        input_cache_read_per_million: 0.4,
-        input_cache_write_per_million: 5,
+  pricing: {
+    tiers: [
+      {
+        start_context_length: 0,
+        pricing: {
+          prompt_per_million: 4,
+          completion_per_million: 24,
+          input_cache_read_per_million: 0.4,
+          input_cache_write_per_million: 5,
+        },
       },
-    },
-    {
-      start_context_length: 272_000,
-      pricing: {
-        prompt_per_million: 8,
-        completion_per_million: 36,
-        input_cache_read_per_million: 0.8,
-        input_cache_write_per_million: 10,
+      {
+        start_context_length: 272_000,
+        pricing: {
+          prompt_per_million: 8,
+          completion_per_million: 36,
+          input_cache_read_per_million: 0.8,
+          input_cache_write_per_million: 10,
+        },
       },
-    },
-  ],
+    ],
+  },
   inference_provider_restriction: [],
 };

apps/web/src/lib/ai-gateway/providers/openrouter/free-endpoint-data-policy.test.ts

@@ -50,17 +50,19 @@ function dataCollectionExclusiveModel(
   inference_provider_restriction: KiloExclusiveModel['inference_provider_restriction']
 ): KiloExclusiveModel {
   const model = freeExclusiveModel(public_id, inference_provider_restriction);
-  model.pricing = [
-    {
-      start_context_length: 0,
-      pricing: {
-        prompt_per_million: 1,
-        completion_per_million: 1,
-        input_cache_read_per_million: null,
-        input_cache_write_per_million: null,
+  model.pricing = {
+    tiers: [
+      {
+        start_context_length: 0,
+        pricing: {
+          prompt_per_million: 1,
+          completion_per_million: 1,
+          input_cache_read_per_million: null,
+          input_cache_write_per_million: null,
+        },
       },
-    },
-  ];
+    ],
+  };
   model.flags = ['requires-data-collection'];
   return model;
 }
@@ -191,17 +193,19 @@ describe('applyFreeEndpointDataPolicy', () => {
     const disabled = freeExclusiveModel('example/model:free', []);
     disabled.status = 'disabled';
     const paid = freeExclusiveModel('example/model:discounted', []);
-    paid.pricing = [
-      {
-        start_context_length: 0,
-        pricing: {
-          prompt_per_million: 1,
-          completion_per_million: 1,
-          input_cache_read_per_million: null,
-          input_cache_write_per_million: null,
+    paid.pricing = {
+      tiers: [
+        {
+          start_context_length: 0,
+          pricing: {
+            prompt_per_million: 1,
+            completion_per_million: 1,
+            input_cache_read_per_million: null,
+            input_cache_write_per_million: null,
+          },
         },
-      },
-    ];
+      ],
+    };
 
     applyFreeEndpointDataPolicy({
       providerModelData: [{ provider: { slug: 'novita' }, models: [model] }],