diff --git a/crates/language_models/src/provider/open_router.rs b/crates/language_models/src/provider/open_router.rs
index 8f2abfce35852c617ddee22de18432908660fe95..aaa0bd620ccf1a961b8c97c0c9fe3ba348b51cca 100644
--- a/crates/language_models/src/provider/open_router.rs
+++ b/crates/language_models/src/provider/open_router.rs
@@ -381,7 +381,7 @@ impl LanguageModel for OpenRouterLanguageModel {
 
     fn tool_input_format(&self) -> LanguageModelToolSchemaFormat {
         let model_id = self.model.id().trim().to_lowercase();
-        if model_id.contains("gemini") || model_id.contains("grok-4") {
+        if model_id.contains("gemini") || model_id.contains("grok") {
             LanguageModelToolSchemaFormat::JsonSchemaSubset
         } else {
             LanguageModelToolSchemaFormat::JsonSchema