feat(cost): add gemini-3.1-flash-image-preview pricing

packages/cost/models/authors/google/gemini-3.1-flash-image-preview/endpoints.ts

@@ -0,0 +1,110 @@
+import { ModelProviderName } from "../../../providers";
+import type { ModelProviderConfig } from "../../../types";
+import { Gemini31FlashImagePreviewModelName } from "./model";
+
+export const endpoints = {
+  "gemini-3.1-flash-image-preview:google-ai-studio": {
+    providerModelId: "gemini-3.1-flash-image-preview",
+    provider: "google-ai-studio",
+    author: "google",
+    pricing: [
+      {
+        threshold: 0,
+        input: 0.00000025, // $0.25/1M tokens
+        output: 0.0000015, // $1.50/1M tokens (text output)
+        image: {
+          input: 0.00000025, // $0.25/1M tokens for image input (same as text)
+          output: 0.00006, // $60/1M tokens for image output ($0.067 per 1K image)
+        },
+      },
+    ],
+    contextLength: 65_536,
+    maxCompletionTokens: 32_768,
+    supportedParameters: [
+      "max_tokens",
+      "response_format",
+      "seed",
+      "stop",
+      "temperature",
+      "top_p",
+    ],
+    rateLimits: {
+      rpm: 100,
+      tpm: 1_000_000,
+    },
+    ptbEnabled: true,
+    responseFormat: "GOOGLE",
+    endpointConfigs: {
+      "*": {},
+    },
+  },
+  "gemini-3.1-flash-image-preview:vertex": {
+    providerModelId: "gemini-3.1-flash-image-preview",
+    provider: "vertex",
+    author: "google",
+    crossRegion: true,
+    pricing: [
+      {
+        threshold: 0,
+        input: 0.00000025, // $0.25/1M tokens
+        output: 0.0000015, // $1.50/1M tokens (text output)
+        image: {
+          input: 0.00000025, // $0.25/1M tokens for image input (same as text)
+          output: 0.00006, // $60/1M tokens for image output
+        },
+      },
+    ],
+    contextLength: 65_536,
+    maxCompletionTokens: 32_768,
+    supportedParameters: [
+      "max_tokens",
+      "response_format",
+      "seed",
+      "stop",
+      "temperature",
+      "top_p",
+    ],
+    responseFormat: "GOOGLE",
+    ptbEnabled: true,
+    endpointConfigs: {
+      global: {
+        providerModelId: "gemini-3.1-flash-image-preview",
+      },
+    },
+  },
+  "gemini-3.1-flash-image-preview:openrouter": {
+    provider: "openrouter",
+    author: "google",
+    providerModelId: "google/gemini-3.1-flash-image-preview",
+    pricing: [
+      {
+        threshold: 0,
+        input: 0.000000264, // $0.264/1M - $0.25/1M * 1.055 (OpenRouter 5.5% markup)
+        output: 0.000001583, // $1.583/1M - $1.50/1M * 1.055
+        image: {
+          input: 0.000000264, // $0.264/1M for image input (with markup)
+          output: 0.0000633, // $63.30/1M - $60/1M * 1.055 for image output
+        },
+      },
+    ],
+    contextLength: 65_536,
+    maxCompletionTokens: 32_768,
+    supportedParameters: [
+      "max_tokens",
+      "response_format",
+      "seed",
+      "stop",
+      "temperature",
+      "top_p",
+    ],
+    ptbEnabled: true,
+    endpointConfigs: {
+      "*": {},
+    },
+  },
+} satisfies Partial<
+  Record<
+    `${Gemini31FlashImagePreviewModelName}:${ModelProviderName}`,
+    ModelProviderConfig
+  >
+>;

packages/cost/models/authors/google/gemini-3.1-flash-image-preview/model.ts

@@ -0,0 +1,17 @@
+import { ModelConfig } from "../../../types";
+
+export const model = {
+  "gemini-3.1-flash-image-preview": {
+    name: "Google Gemini 3.1 Flash Image Preview",
+    author: "google",
+    description:
+      "Gemini 3.1 Flash Image is Google's fast and cost-effective image generation model. It supports text and image inputs with text and image outputs, optimized for high-throughput image generation at lower cost than Gemini 3 Pro Image. This preview version supports native image generation with token-based pricing.",
+    contextLength: 65_536,
+    maxOutputTokens: 32_768,
+    created: "2026-01-15T00:00:00",
+    modality: { inputs: ["text", "image"], outputs: ["text", "image"] },
+    tokenizer: "Gemini",
+  },
+} satisfies Record<string, ModelConfig>;
+
+export type Gemini31FlashImagePreviewModelName = keyof typeof model;

packages/cost/models/authors/google/index.ts

@@ -19,6 +19,8 @@ import { model as gemini3FlashPreviewModel } from "./gemini-3-flash-preview/mode
 import { endpoints as gemini3FlashPreviewEndpoints } from "./gemini-3-flash-preview/endpoints";
 import { model as gemini3ProImagePreviewModel } from "./gemini-3-pro-image/model";
 import { endpoints as gemini3ProImagePreviewEndpoints } from "./gemini-3-pro-image/endpoints";
+import { model as gemini31FlashImagePreviewModel } from "./gemini-3.1-flash-image-preview/model";
+import { endpoints as gemini31FlashImagePreviewEndpoints } from "./gemini-3.1-flash-image-preview/endpoints";
 import { model as gemma29bModel } from "./gemma/model";
 import { endpoints as gemma29bEndpoints } from "./gemma/endpoints";
 import { model as gemma3Model } from "./gemma-3/model";
@@ -34,6 +36,7 @@ export const googleModels = {
   ...gemini31ProPreviewModel,
   ...gemini3FlashPreviewModel,
   ...gemini3ProImagePreviewModel,
+  ...gemini31FlashImagePreviewModel,
   ...gemma29bModel,
   ...gemma3Model,
 } satisfies Record<string, ModelConfig>;
@@ -47,6 +50,7 @@ export const googleEndpointConfig = {
   ...gemini31ProPreviewEndpoints,
   ...gemini3FlashPreviewEndpoints,
   ...gemini3ProImagePreviewEndpoints,
+  ...gemini31FlashImagePreviewEndpoints,
   ...gemma29bEndpoints,
   ...gemma3Endpoints,
 } satisfies Record<string, ModelProviderConfig>;

packages/cost/providers/google/index.ts

@@ -263,6 +263,16 @@ export const costs: ModelRow[] = [
       prompt_cache_read_token: 0.0000002, // $0.20/1M = 10% of input
     },
   },
+  {
+    model: {
+      operator: "includes",
+      value: "gemini-3.1-flash-image-preview",
+    },
+    cost: {
+      prompt_token: 0.00000025, // $0.25/1M tokens
+      completion_token: 0.0000015, // $1.50/1M tokens (text output)
+    },
+  },
 ];
 
 export const modelDetails: ModelDetailsMap = {