feat: router priority queue (#6010)

Signed-off-by: PeaBrane <yanrpei@gmail.com>
Co-authored-by: ishandhanani <82981111+ishandhanani@users.noreply.github.com>

lib/llm/src/protocols/common/preprocessor.rs

@@ -51,6 +51,12 @@ pub struct RoutingHints {
     /// Used for LORA-aware routing and tracking.
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub lora_name: Option<String>,
+
+    /// Priority jump in seconds for queue ordering.
+    /// A positive value decreases the effective arrival time, moving the request
+    /// ahead in the scheduler queue.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub priority_jump: Option<f64>,
 }
 
 #[derive(Serialize, Deserialize, Debug, Clone, Default)]

lib/llm/src/protocols/openai/nvext.rs

@@ -180,11 +180,27 @@ pub struct NvExt {
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub enable_local_updates: Option<bool>,
 
-    /// Expected number of output tokens for this request.
-    /// Used as a hint for routing decisions to estimate resource requirements.
+    /// Agent-provided hints for request handling.
     #[builder(default, setter(strip_option))]
     #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub expected_output_tokens: Option<u32>,
+    pub agent_hints: Option<AgentHints>,
+}
+
+/// Hints from the agent/caller about request characteristics.
+#[derive(ToSchema, Serialize, Deserialize, Builder, Debug, Clone, Default)]
+pub struct AgentHints {
+    /// Latency sensitivity in seconds for queue ordering.
+    /// Higher values cause the request to be scheduled sooner when the router queue is enabled.
+    #[builder(default, setter(strip_option))]
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub latency_sensitivity: Option<f64>,
+
+    /// Expected output sequence length (number of output tokens).
+    /// Used as a hint for routing decisions to estimate resource requirements
+    /// and for output block tracking decay.
+    #[builder(default, setter(strip_option))]
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub osl: Option<u32>,
 }
 
 impl Default for NvExt {
@@ -234,7 +250,6 @@ mod tests {
         assert_eq!(nv_ext.prefill_worker_id, None);
         assert_eq!(nv_ext.decode_worker_id, None);
         assert_eq!(nv_ext.enable_local_updates, None);
-        assert_eq!(nv_ext.expected_output_tokens, None);
     }
 
     // Test valid builder configurations