diff --git a/src/cliproxy/model-catalog.ts b/src/cliproxy/model-catalog.ts
index 3671eb6c..8a4e4564 100644
--- a/src/cliproxy/model-catalog.ts
+++ b/src/cliproxy/model-catalog.ts
@@ -11,24 +11,14 @@ import {
   migrateDeniedAntigravityModelAliases,
   normalizeModelIdForProvider,
 } from './model-id-normalizer';
+import {
+  AGY_GEMINI_PRO_COMPATIBILITY_IDS,
+  AGY_GEMINI_PRO_HIGH_ID,
+  AGY_GEMINI_PRO_LOW_ID,
+} from '../shared/agy-gemini-pro-compatibility';
 import { stripModelConfigurationSuffixes } from '../shared/extended-context-utils';
 import { GEMINI_MINOR_VERSION_COMPATIBILITY_IDS } from '../shared/gemini-minor-version-compatibility';
 
-const AGY_GEMINI_PRO_HIGH_ID = 'gemini-3.1-pro-high';
-const AGY_GEMINI_PRO_LOW_ID = 'gemini-3.1-pro-low';
-const AGY_GEMINI_PRO_COMPATIBILITY_IDS = Object.freeze({
-  'gemini-3-pro-high': AGY_GEMINI_PRO_HIGH_ID,
-  'gemini-3.1-pro-high': AGY_GEMINI_PRO_HIGH_ID,
-  'gemini-3-pro-low': AGY_GEMINI_PRO_LOW_ID,
-  'gemini-3.1-pro-low': AGY_GEMINI_PRO_LOW_ID,
-  'gemini-3-pro-preview': AGY_GEMINI_PRO_HIGH_ID,
-  'gemini-3-pro-preview-customtools': AGY_GEMINI_PRO_HIGH_ID,
-  'gemini-3.1-pro-preview': AGY_GEMINI_PRO_HIGH_ID,
-  'gemini-3.1-pro-preview-customtools': AGY_GEMINI_PRO_HIGH_ID,
-  'gemini-3-1-pro-preview': AGY_GEMINI_PRO_HIGH_ID,
-  'gemini-3-1-pro-preview-customtools': AGY_GEMINI_PRO_HIGH_ID,
-} satisfies Record<string, string>);
-
 /**
  * Thinking support configuration for a model.
  * Defines how thinking/reasoning budget can be controlled.
diff --git a/src/shared/agy-gemini-pro-compatibility.ts b/src/shared/agy-gemini-pro-compatibility.ts
new file mode 100644
index 00000000..88b4215d
--- /dev/null
+++ b/src/shared/agy-gemini-pro-compatibility.ts
@@ -0,0 +1,15 @@
+export const AGY_GEMINI_PRO_HIGH_ID = 'gemini-3.1-pro-high';
+export const AGY_GEMINI_PRO_LOW_ID = 'gemini-3.1-pro-low';
+
+export const AGY_GEMINI_PRO_COMPATIBILITY_IDS = Object.freeze({
+  'gemini-3-pro-high': AGY_GEMINI_PRO_HIGH_ID,
+  'gemini-3.1-pro-high': AGY_GEMINI_PRO_HIGH_ID,
+  'gemini-3-pro-low': AGY_GEMINI_PRO_LOW_ID,
+  'gemini-3.1-pro-low': AGY_GEMINI_PRO_LOW_ID,
+  'gemini-3-pro-preview': AGY_GEMINI_PRO_HIGH_ID,
+  'gemini-3-pro-preview-customtools': AGY_GEMINI_PRO_HIGH_ID,
+  'gemini-3.1-pro-preview': AGY_GEMINI_PRO_HIGH_ID,
+  'gemini-3.1-pro-preview-customtools': AGY_GEMINI_PRO_HIGH_ID,
+  'gemini-3-1-pro-preview': AGY_GEMINI_PRO_HIGH_ID,
+  'gemini-3-1-pro-preview-customtools': AGY_GEMINI_PRO_HIGH_ID,
+} satisfies Record<string, string>);
diff --git a/ui/src/lib/model-catalogs.ts b/ui/src/lib/model-catalogs.ts
index ad809f3c..ab6425e8 100644
--- a/ui/src/lib/model-catalogs.ts
+++ b/ui/src/lib/model-catalogs.ts
@@ -5,24 +5,15 @@
 
 import type { ModelEntry, ProviderCatalog } from '@/components/cliproxy/provider-model-selector';
 import { stripModelConfigurationSuffixes } from '@/lib/extended-context-utils';
+import {
+  AGY_GEMINI_PRO_COMPATIBILITY_IDS,
+  AGY_GEMINI_PRO_HIGH_ID,
+  AGY_GEMINI_PRO_LOW_ID,
+} from '@shared/agy-gemini-pro-compatibility';
 import { GEMINI_MINOR_VERSION_COMPATIBILITY_IDS } from '@shared/gemini-minor-version-compatibility';
 
 const GEMINI_PREVIEW_MODEL_ID_PATTERN =
   /^gemini-(\d+(?:[.-]\d+)*)-(pro|flash)-preview(-customtools)?$/i;
-const AGY_GEMINI_PRO_HIGH_ID = 'gemini-3.1-pro-high';
-const AGY_GEMINI_PRO_LOW_ID = 'gemini-3.1-pro-low';
-const AGY_GEMINI_PRO_COMPATIBILITY_IDS = new Map<string, string>([
-  ['gemini-3-pro-high', AGY_GEMINI_PRO_HIGH_ID],
-  ['gemini-3.1-pro-high', AGY_GEMINI_PRO_HIGH_ID],
-  ['gemini-3-pro-low', AGY_GEMINI_PRO_LOW_ID],
-  ['gemini-3.1-pro-low', AGY_GEMINI_PRO_LOW_ID],
-  ['gemini-3-pro-preview', AGY_GEMINI_PRO_HIGH_ID],
-  ['gemini-3-pro-preview-customtools', AGY_GEMINI_PRO_HIGH_ID],
-  ['gemini-3.1-pro-preview', AGY_GEMINI_PRO_HIGH_ID],
-  ['gemini-3.1-pro-preview-customtools', AGY_GEMINI_PRO_HIGH_ID],
-  ['gemini-3-1-pro-preview', AGY_GEMINI_PRO_HIGH_ID],
-  ['gemini-3-1-pro-preview-customtools', AGY_GEMINI_PRO_HIGH_ID],
-]);
 const MANAGED_MODEL_PREFIXES = ['agy/', 'gcli/'] as const;
 
 export type CatalogAvailableModel = {
@@ -62,7 +53,7 @@ function stripCustomtoolsSuffix(modelId: string): string {
 }
 
 function getAgyGeminiProCompatibilityId(modelId: string): string | undefined {
-  return AGY_GEMINI_PRO_COMPATIBILITY_IDS.get(normalizeModelId(modelId));
+  return AGY_GEMINI_PRO_COMPATIBILITY_IDS[normalizeModelId(modelId)];
 }
 
 function parseGeminiPreviewModelId(modelId: string): GeminiPreviewModelInfo | null {
@@ -208,8 +199,8 @@ export const MODEL_CATALOGS: Record<string, ProviderCatalog> = {
         extendedContext: true,
         presetMapping: {
           default: 'gemini-3-1-flash-preview',
-          opus: 'gemini-3.1-pro-preview',
-          sonnet: 'gemini-3.1-pro-preview',
+          opus: AGY_GEMINI_PRO_HIGH_ID,
+          sonnet: AGY_GEMINI_PRO_HIGH_ID,
           haiku: 'gemini-3-1-flash-preview',
         },
       },
diff --git a/ui/tests/unit/ui/lib/preset-utils.test.ts b/ui/tests/unit/ui/lib/preset-utils.test.ts
index 2049860a..b527c51d 100644
--- a/ui/tests/unit/ui/lib/preset-utils.test.ts
+++ b/ui/tests/unit/ui/lib/preset-utils.test.ts
@@ -158,6 +158,12 @@ describe('claude preset utils', () => {
     expect(resolvedAgyModels.find((model) => model.name === 'Gemini Flash')?.id).toBe(
       'gemini-3-1-flash-preview'
     );
+    expect(resolvedAgyModels.find((model) => model.name === 'Gemini Flash')?.presetMapping).toEqual(
+      expect.objectContaining({
+        opus: 'gemini-3.1-pro-high',
+        sonnet: 'gemini-3.1-pro-high',
+      })
+    );
 
     const supplementalAgyModels = getSupplementalCatalogModels(
       'agy',