diff --git a/src/plugin/transform/gemini.ts b/src/plugin/transform/gemini.ts
index 65e0766..3c2f359 100644
--- a/src/plugin/transform/gemini.ts
+++ b/src/plugin/transform/gemini.ts
@@ -284,8 +284,17 @@ export function normalizeGeminiTools(payload: RequestPayload): {
       `tool-${toolIndex}`;
 
     // Always update function.input_schema with transformed schema
+    // CRITICAL: This must happen BEFORE custom creation so function tools
+    // keep their schema even after custom is stripped (line 332).
     if (newTool.function && schema) {
       (newTool.function as Record<string, unknown>).input_schema = schema;
+    } else if (newTool.function && !schema) {
+      // Ensure function always has a schema even if source had none
+      (newTool.function as Record<string, unknown>).input_schema = {
+        type: "OBJECT",
+        properties: {},
+      };
+      toolDebugMissing += 1;
     }
 
     // Always update custom.input_schema with transformed schema
@@ -293,7 +302,7 @@ export function normalizeGeminiTools(payload: RequestPayload): {
       (newTool.custom as Record<string, unknown>).input_schema = schema;
     }
 
-    // Create custom from function if missing
+    // Create custom from function if missing (temporary, stripped later)
     if (!newTool.custom && newTool.function) {
       const fn = newTool.function as Record<string, unknown>;
       newTool.custom = {
diff --git a/src/plugin/transform/model-resolver.ts b/src/plugin/transform/model-resolver.ts
index b6a5451..598448b 100644
--- a/src/plugin/transform/model-resolver.ts
+++ b/src/plugin/transform/model-resolver.ts
@@ -48,6 +48,12 @@ export const MODEL_ALIASES: Record<string, string> = {
   "gemini-3-flash-medium": "gemini-3-flash",
   "gemini-3-flash-high": "gemini-3-flash",
 
+  // Marketing aliases - map to real API model names
+  "gemini-omni-flash-preview": "gemini-3-flash",
+  "gemini-omni-flash": "gemini-3-flash",
+  "gemini-omni-pro-preview": "gemini-3-pro",
+  "gemini-omni-pro": "gemini-3-pro",
+
   // Gemini 3.5 Flash - upstream uses tiered names (no bare model exists).
   // Each tier maps to a distinct upstream model ID (probed 200 OK).
   "gemini-3.5-flash": "gemini-3.5-flash-low", // default → Medium tier