feat: proxy demo

Signed-off-by: Greg Clark <grclark@nvidia.com>

Author: messiaen

Cargo.lock

@@ -12,6 +12,7 @@ members = [
     "crates/switchyard-py",
     "crates/switchyard-server",
     "crates/switchyard-translation",
+    "demo/libsy-proxy",
 ]
 
 [workspace.package]

Cargo.toml

@@ -42,7 +42,10 @@ impl LlmClient for StubClient {
             format!("answer from {model}")
         };
         Ok(OrchestratorResponse {
-            llm_response: LlmResponse { completion },
+            llm_response: LlmResponse {
+                completion,
+                raw_response: None,
+            },
             metadata: None,
         })
     }

crates/libsy/examples/research_agent.rs

@@ -34,7 +34,10 @@ async fn call_model(request: &OrchestratorRequest) -> OrchestratorResponse {
         format!("answer from {model}")
     };
     OrchestratorResponse {
-        llm_response: LlmResponse { completion },
+        llm_response: LlmResponse {
+            completion,
+            raw_response: None,
+        },
         metadata: None,
     }
 }

crates/libsy/examples/research_agent_core.rs

@@ -50,6 +50,9 @@ pub struct AgentSysSignals {}
 #[derive(Clone)]
 pub struct LlmResponse {
     pub completion: String,
+    /// Optional raw provider response body, so a host (e.g. a proxy) can forward
+    /// the upstream response losslessly instead of rebuilding it from `completion`.
+    pub raw_response: Option<serde_json::Value>,
 }
 
 #[derive(Clone)]
@@ -452,6 +455,7 @@ mod tests {
             Ok(OrchestratorResponse {
                 llm_response: LlmResponse {
                     completion: model_name.unwrap_or_default(),
+                    raw_response: None,
                 },
                 metadata: None,
             })
@@ -582,6 +586,7 @@ mod tests {
                             .set_response(Ok(OrchestratorResponse {
                                 llm_response: LlmResponse {
                                     completion: "fulfilled".to_string(),
+                                    raw_response: None,
                                 },
                                 metadata: None,
                             }))
@@ -695,6 +700,7 @@ mod tests {
                 Ok(OrchestratorResponse {
                     llm_response: LlmResponse {
                         completion: model_name.unwrap_or_default(),
+                        raw_response: None,
                     },
                     metadata: None,
                 })

crates/libsy/src/lib.rs

@@ -226,7 +226,10 @@ mod tests {
             };
             self.seen.lock().map_err(|_| "lock poisoned")?.push(request);
             Ok(OrchestratorResponse {
-                llm_response: LlmResponse { completion },
+                llm_response: LlmResponse {
+                    completion,
+                    raw_response: None,
+                },
                 metadata: None,
             })
         }

crates/libsy/src/llm_class.rs

@@ -128,6 +128,7 @@ mod tests {
             Ok(OrchestratorResponse {
                 llm_response: LlmResponse {
                     completion: model_name.unwrap_or_default(),
+                    raw_response: None,
                 },
                 metadata: None,
             })

crates/libsy/src/rand.rs

@@ -0,0 +1,23 @@
+# SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+[package]
+name = "libsy-proxy"
+version = "0.1.0"
+description = "Demo LLM proxy: switchyard HTTP + API translation, libsy classifier routing"
+authors.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+rust-version.workspace = true
+
+[dependencies]
+libsy = { path = "../../crates/libsy" }
+switchyard-core = { path = "../../crates/switchyard-core" }
+switchyard-components = { path = "../../crates/switchyard-components" }
+switchyard-components-v2 = { path = "../../crates/switchyard-components-v2" }
+switchyard-server = { path = "../../crates/switchyard-server" }
+
+async-trait = "0.1"
+serde_json = "1"
+tokio = { version = "1", features = ["macros", "rt-multi-thread", "net", "signal"] }