Fix image generation: use stable Gemini image keys

OpenRouter retired the "-preview" Gemini image keys; their remaining
endpoints no longer advertise image output, so every image request
failed with "404 No endpoints found that support the requested output
modalities: text, image". Switch the catalog and pinned tool models to
the republished stable keys:
  google/gemini-3.1-flash-image-preview -> google/gemini-3.1-flash-image
  google/gemini-3-pro-image-preview     -> google/gemini-3-pro-image

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: hatton

components/tools/ImageTool.tsx

@@ -41,10 +41,10 @@ import { DEFAULT_SIZE_TOKEN, pickSizeTokenForLongEdge } from "../../lib/imageSiz
 import { ToolModelPicker } from "./ToolModelPicker";
 import { theme } from "../../themes";
 
-// Must match the catalog id in data/models-registry.json5, which is the
-// "-preview" key while OpenRouter only exposes the preview. Keep in sync if the
-// non-preview key is ever published and the registry id is updated.
-const GEMINI_3_1_FLASH_MODEL_ID = "google/gemini-3.1-flash-image-preview";
+// Must match the catalog id in data/models-registry.json5 (the stable,
+// non-preview key now that OpenRouter has retired the "-preview" key). Keep in
+// sync if the registry id changes.
+const GEMINI_3_1_FLASH_MODEL_ID = "google/gemini-3.1-flash-image";
 
 const LOCALIZE_TOOL_ORDER = [
   "extract_cast_of_characters",

components/tools/tools-registry.ts

@@ -580,8 +580,8 @@ export const TOOLS: ToolDefinition[] = (
       referenceImages: "0",
       // Only offer these two engines: Gemini 3 Pro Preview (default) and
       // GPT-5.4 Image 2 as a secondary option. Other catalog models are hidden.
-      modelIds: ["google/gemini-3-pro-image-preview", "openai/gpt-5.4-image-2"],
-      recommendedModelIds: ["google/gemini-3-pro-image-preview"],
+      modelIds: ["google/gemini-3-pro-image", "openai/gpt-5.4-image-2"],
+      recommendedModelIds: ["google/gemini-3-pro-image"],
     },
     {
       id: "remove_object",

data/models-registry.json5

@@ -2,7 +2,7 @@
 // Add comments, trailing commas, etc.
 [
   {
-    id: "google/gemini-3-pro-image-preview",
+    id: "google/gemini-3-pro-image",
     name: "Gemini 3 Pro Preview",
     badge: "Great but Expensive",
     description: "'Nano Banana Pro' Good for editing, as it preserves the original image.",
@@ -26,14 +26,11 @@
     default: false,
   },
   {
-    // OpenRouter currently only exposes the "-preview" key. We can NOT pre-list
-    // the not-yet-published "google/gemini-3.1-flash-image" as a fallbackId:
-    // OpenRouter validates every id in the `models` array up front and rejects
-    // the whole request with 400 ("... is not a valid model ID") for any key it
-    // doesn't recognize. (The `models` fallback only fails over on runtime
-    // errors of *valid* models, not unknown ids.) When OpenRouter retires the
-    // preview and republishes the non-preview key, update `id` here.
-    id: "google/gemini-3.1-flash-image-preview",
+    // OpenRouter retired the "-preview" key and republished the stable
+    // "google/gemini-3.1-flash-image" key (the preview now has no
+    // image-output endpoint, surfacing as "404 No endpoints found that support
+    // the requested output modalities: text, image"). Use the stable key.
+    id: "google/gemini-3.1-flash-image",
     name: "Gemini 3.1 Flash",
     badge: "Great",
     description: "'Nano Banana 2'. Good for editing, as it preserves the original image. Not quite as good at instruction understanding as Gemini 3 Pro.",

lib/__tests__/modelSelection.test.ts

@@ -11,7 +11,7 @@ import {
 } from "../modelsCatalog";
 import type { ToolDefinition } from "../../types";
 
-const GEMINI_FLASH = "google/gemini-3.1-flash-image-preview";
+const GEMINI_FLASH = "google/gemini-3.1-flash-image";
 const GPT5_IMAGE = "openai/gpt-5-image";
 const GPT54_IMAGE_2 = "openai/gpt-5.4-image-2";
 

tests/experiments/cdp-run.mjs

@@ -130,9 +130,9 @@ await page.evaluate((level) => {
     const state = JSON.parse(RAW);
     state.modelReasoningLevels = state.modelReasoningLevels || {};
     if (level === "default") {
-      delete state.modelReasoningLevels["google/gemini-3-pro-image-preview"];
+      delete state.modelReasoningLevels["google/gemini-3-pro-image"];
     } else {
-      state.modelReasoningLevels["google/gemini-3-pro-image-preview"] = level;
+      state.modelReasoningLevels["google/gemini-3-pro-image"] = level;
     }
     localStorage.setItem("imageToolsAppState.v1", JSON.stringify(state));
     return "ok";

tests/experiments/gemini-grid-experiment.mjs

@@ -18,7 +18,7 @@ const INPUT = process.env.INPUT_IMAGE
 const OUT_IMAGE = path.resolve(here, "output-grid.png");
 const OUT_TEXT = path.resolve(here, "output-text.txt");
 
-const MODEL = process.env.EXPERIMENT_MODEL || "google/gemini-3.1-flash-image-preview";
+const MODEL = process.env.EXPERIMENT_MODEL || "google/gemini-3.1-flash-image";
 const KEY = process.env.BLOOM_OPENROUTER_KEY_FOR_PLAYWRIGHT_TESTS;
 
 const PROMPT = `This image is a single page containing several separate illustrated panels (a comic / instructional poster). Do TWO things.