diff --git a/crates/libsy-llm-client/src/backend.rs b/crates/libsy-llm-client/src/backend.rs
index 0c5d72854..95de23411 100644
--- a/crates/libsy-llm-client/src/backend.rs
+++ b/crates/libsy-llm-client/src/backend.rs
@@ -24,6 +24,7 @@ const OPENAI_OVERFLOW_PHRASES: &[&str] = &[
     "context window",
     "context length is only",
     "please reduce the length of the input",
+    "exceeds the maximum allowed input length",
 ];
 
 // Anthropic has no structured `error.code`, so detection is phrase-based only.
@@ -310,6 +311,10 @@ mod tests {
             r#"{"error":{"message":"the model's context length is only 131072 tokens"}}"#
         ));
         assert!(!backend.is_context_overflow(r#"{"error":{"code":"invalid_api_key"}}"#));
+        // Hub GLM (LiteLLM-wrapped): code is "400", detection relies on phrase match.
+        assert!(backend.is_context_overflow(
+            r#"{"error":{"message":"Input length 877338 exceeds the maximum allowed input length of 639968 tokens","code":"400"}}"#
+        ));
     }
 
     #[test]
diff --git a/crates/switchyard-components/src/backends/openai.rs b/crates/switchyard-components/src/backends/openai.rs
index 0f9fc7d7d..7cdaf5550 100644
--- a/crates/switchyard-components/src/backends/openai.rs
+++ b/crates/switchyard-components/src/backends/openai.rs
@@ -528,6 +528,7 @@ const OPENAI_OVERFLOW_PHRASES: &[&str] = &[
     "context window",
     "context length is only",
     "please reduce the length of the input",
+    "exceeds the maximum allowed input length",
 ];
 
 fn is_context_overflow(body: &str) -> bool {
@@ -759,6 +760,14 @@ mod tests {
         assert!(!is_context_overflow(body));
     }
 
+    #[test]
+    fn context_overflow_hub_glm_matches() {
+        // Hub GLM error via LiteLLM: code is "400" (not context_length_exceeded),
+        // so detection relies on phrase matching.
+        let body = r#"{"error":{"message":"Input length 877338 exceeds the maximum allowed input length of 639968 tokens","code":"400"}}"#;
+        assert!(is_context_overflow(body));
+    }
+
     #[test]
     fn context_overflow_nvidia_litellm_wrap_matches() {
         // Body shape observed from inference-api.nvidia.com's LiteLLM proxy