diff --git a/src/protocols/spec.rs b/src/protocols/spec.rs
index 3ed54dc8..30d5fb97 100644
--- a/src/protocols/spec.rs
+++ b/src/protocols/spec.rs
@@ -517,7 +517,7 @@ pub struct ChatCompletionRequest {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub echo: Option<bool>,
 
-    /// Reasoning effort level for reasoning models (low, medium, high)
+    /// Reasoning effort level supported by OpenAI-compatible vLLM servers.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub reasoning_effort: Option<ReasoningEffort>,
 
@@ -855,9 +855,14 @@ fn default_reasoning_effort() -> Option<ReasoningEffort> {
 #[derive(Debug, Clone, Deserialize, Serialize)]
 #[serde(rename_all = "snake_case")]
 pub enum ReasoningEffort {
+    None,
+    Minimal,
     Low,
     Medium,
     High,
+    #[serde(rename = "xhigh")]
+    XHigh,
+    Max,
 }
 
 // ============= Input/Output Items =============
diff --git a/tests/test_openai_routing.rs b/tests/test_openai_routing.rs
index f8c2b9e9..d9b7424f 100644
--- a/tests/test_openai_routing.rs
+++ b/tests/test_openai_routing.rs
@@ -471,3 +471,24 @@ async fn test_openai_router_chat_with_reasoning_fields() {
     // Verify it's a valid chat completion response
     assert_eq!(chat_response["object"], "chat.completion");
 }
+
+#[test]
+fn reasoning_effort_accepts_current_vllm_values() {
+    for value in ["none", "minimal", "low", "medium", "high", "xhigh", "max"] {
+        let request: vllm_router_rs::protocols::spec::ChatCompletionRequest =
+            serde_json::from_value(serde_json::json!({
+                "model": "test-model",
+                "messages": [{"role": "user", "content": "hello"}],
+                "reasoning_effort": value
+            }))
+            .unwrap();
+        assert_eq!(
+            serde_json::to_value(request).unwrap()["reasoning_effort"],
+            value
+        );
+
+        let reasoning: vllm_router_rs::protocols::spec::ResponseReasoningParam =
+            serde_json::from_value(serde_json::json!({"effort": value})).unwrap();
+        assert_eq!(serde_json::to_value(reasoning).unwrap()["effort"], value);
+    }
+}