fix(gemini): normalize mixed tools for same-format providers

crates/aether-ai/formats/src/formats/gemini/generate_content/request.rs

@@ -218,6 +218,18 @@ fn enable_server_side_tool_invocations_for_mixed_tools(
     if !gemini_model_supports_mixed_tools(mapped_model) {
         return None;
     }
+    ensure_server_side_tool_invocations_for_mixed_tools(output)
+}
+
+pub fn ensure_server_side_tool_invocations_for_mixed_tools(output: &mut Value) -> Option<()> {
+    let output_object = output.as_object_mut()?;
+    let tools = output_object.get("tools").and_then(Value::as_array);
+    let Some(tools) = tools else {
+        return Some(());
+    };
+    if !gemini_tools_are_mixed(tools) {
+        return Some(());
+    }
 
     let tool_config = output_object
         .entry("toolConfig".to_string())

crates/aether-ai/formats/src/lib.rs

@@ -12,6 +12,7 @@ pub use formats::context::{
     ConversionFieldRecord, ConversionFieldStatus, ConversionReport, Converted, FormatContext,
     FormatError,
 };
+pub use formats::gemini::generate_content::request::ensure_server_side_tool_invocations_for_mixed_tools;
 pub use formats::id::{
     api_format_alias_matches, api_format_defaults_to_client_error_failover,
     api_format_defaults_to_non_stream, api_format_permission_covers,