feat(acp): route session/setTitle to the new schema types

Cargo.toml

@@ -37,7 +37,7 @@ agent-client-protocol-trace-viewer = { path = "src/agent-client-protocol-trace-v
 yopo = { package = "agent-client-protocol-yopo", path = "src/yopo" }
 
 # Protocol
-agent-client-protocol-schema = { version = "=1.1.0", features = ["tracing"] }
+agent-client-protocol-schema = { version = "=1.2.0", features = ["tracing"] }
 
 # Core async runtime
 tokio = { version = "1.52", default-features = false }
@@ -113,3 +113,7 @@ struct_field_names = "allow"
 too_many_lines = "allow"
 type_complexity = "allow"
 wildcard_imports = "allow"
+
+[patch.crates-io]
+# Temporary: consume session/setTitle schema types before they are released.
+agent-client-protocol-schema = { git = "https://github.com/daniel-agentee/agent-client-protocol", rev = "064ee1ffe194cdb14e1d45d66875ce74a14933c3" }

src/agent-client-protocol-test/src/testy.rs

@@ -31,7 +31,7 @@ use agent_client_protocol::schema::v1::{
     CompleteElicitationNotification, CreateElicitationRequest, ElicitationAction,
     ElicitationCapabilities, ElicitationFormMode, ElicitationRequestScope, ElicitationSchema,
     ElicitationSessionScope, ElicitationUrlMode, ErrorCode, MultiSelectPropertySchema, RequestId,
-    StringPropertySchema, UrlElicitationRequiredData, UrlElicitationRequiredItem,
+    StringPropertySchema,
 };
 use agent_client_protocol::{
     Agent, Client, ConnectTo, ConnectionTo, JsonRpcRequest, Responder, SentRequest,
@@ -637,7 +637,7 @@ impl Testy {
             Err(error) => {
                 self.finish_prompt(&session_id, StopReason::EndTurn);
                 #[cfg(feature = "unstable")]
-                if error.code == ErrorCode::UrlElicitationRequired {
+                if is_url_elicitation_required_error(&error) {
                     return responder.respond_with_error(error);
                 }
                 return Err(error);
@@ -1765,15 +1765,28 @@ fn elicitation_cancelled(agent: &Testy, session_id: &SessionId, report: &mut Vec
 
 #[cfg(feature = "unstable")]
 fn url_elicitation_required_error() -> agent_client_protocol::Error {
-    let data = UrlElicitationRequiredData::new(vec![UrlElicitationRequiredItem::new(
-        "testy-url-required",
-        "https://example.com/testy/required",
-        "Complete the Testy URL elicitation before continuing",
-    )]);
-    match serde_json::to_value(data) {
-        Ok(data) => agent_client_protocol::Error::url_elicitation_required().data(data),
-        Err(error) => agent_client_protocol::Error::into_internal_error(error),
-    }
+    agent_client_protocol::Error::invalid_params().data(url_elicitation_required_data())
+}
+
+#[cfg(feature = "unstable")]
+fn is_url_elicitation_required_error(error: &agent_client_protocol::Error) -> bool {
+    error.code == ErrorCode::InvalidParams
+        && error
+            .data
+            .as_ref()
+            .is_some_and(|data| data.get("elicitations").is_some())
+}
+
+#[cfg(feature = "unstable")]
+fn url_elicitation_required_data() -> serde_json::Value {
+    serde_json::json!({
+        "elicitations": [{
+            "mode": "url",
+            "elicitationId": "testy-url-required",
+            "url": "https://example.com/testy/required",
+            "message": "Complete the Testy URL elicitation before continuing"
+        }]
+    })
 }
 
 fn send_session_update(

src/agent-client-protocol-test/tests/testy.rs

@@ -12,7 +12,7 @@ use agent_client_protocol::schema::v1::{
     CompleteElicitationNotification, CreateElicitationRequest, CreateElicitationResponse,
     ElicitationAcceptAction, ElicitationAction, ElicitationCapabilities, ElicitationContentValue,
     ElicitationFormCapabilities, ElicitationMode, ElicitationScope, ElicitationUrlCapabilities,
-    ErrorCode, UrlElicitationRequiredData,
+    ErrorCode,
 };
 use agent_client_protocol::{
     Client, Responder,
@@ -1958,18 +1958,18 @@ async fn testy_callbacks_with_unstable_feature_returns_url_required_when_url_eli
                 .block_task()
                 .await
                 .expect_err("url-required elicitation scenario should fail the prompt request");
-            assert_eq!(error.code, ErrorCode::UrlElicitationRequired);
-
-            let data: UrlElicitationRequiredData =
-                serde_json::from_value(error.data.expect("url-required error should include data"))
-                    .expect("url-required error data should deserialize");
-            assert_eq!(data.elicitations.len(), 1);
-            let elicitation = &data.elicitations[0];
-            assert_eq!(elicitation.elicitation_id.to_string(), "testy-url-required");
-            assert_eq!(elicitation.url, "https://example.com/testy/required");
+            assert_eq!(error.code, ErrorCode::InvalidParams);
+
             assert_eq!(
-                elicitation.message,
-                "Complete the Testy URL elicitation before continuing"
+                error.data.expect("url-required error should include data"),
+                serde_json::json!({
+                    "elicitations": [{
+                        "mode": "url",
+                        "elicitationId": "testy-url-required",
+                        "url": "https://example.com/testy/required",
+                        "message": "Complete the Testy URL elicitation before continuing"
+                    }]
+                })
             );
             Ok(())
         })

src/agent-client-protocol/src/capabilities.rs

@@ -142,7 +142,7 @@ mod tests {
 
     #[test]
     fn test_add_capability_to_request() {
-        let request = InitializeRequest::new(ProtocolVersion::LATEST);
+        let request = InitializeRequest::new(ProtocolVersion::V1);
 
         let request = request.add_meta_capability(TestCapability);
 
@@ -165,8 +165,8 @@ mod tests {
         );
         let client_capabilities = ClientCapabilities::new().meta(meta);
 
-        let request = InitializeRequest::new(ProtocolVersion::LATEST)
-            .client_capabilities(client_capabilities);
+        let request =
+            InitializeRequest::new(ProtocolVersion::V1).client_capabilities(client_capabilities);
 
         let request = request.remove_meta_capability(TestCapability);
 
@@ -175,7 +175,7 @@ mod tests {
 
     #[test]
     fn test_add_capability_to_response() {
-        let response = InitializeResponse::new(ProtocolVersion::LATEST);
+        let response = InitializeResponse::new(ProtocolVersion::V1);
 
         let response = response.add_meta_capability(TestCapability);
 
@@ -198,8 +198,8 @@ mod tests {
         );
         let client_capabilities = ClientCapabilities::new().meta(meta);
 
-        let request = InitializeRequest::new(ProtocolVersion::LATEST)
-            .client_capabilities(client_capabilities);
+        let request =
+            InitializeRequest::new(ProtocolVersion::V1).client_capabilities(client_capabilities);
 
         assert!(!request.has_meta_capability(TestCapability));
     }
@@ -216,8 +216,8 @@ mod tests {
         );
         let client_capabilities = ClientCapabilities::new().meta(meta);
 
-        let request = InitializeRequest::new(ProtocolVersion::LATEST)
-            .client_capabilities(client_capabilities);
+        let request =
+            InitializeRequest::new(ProtocolVersion::V1).client_capabilities(client_capabilities);
 
         assert!(!request.has_meta_capability(TestCapability));
     }

src/agent-client-protocol/src/jsonrpc/protocol_compat.rs

@@ -536,7 +536,11 @@ mod imp {
     }
 
     fn public_to_v2_message(message: UntypedMessage) -> Result<UntypedMessage, crate::Error> {
-        let UntypedMessage { method, params } = message;
+        let UntypedMessage { method, mut params } = message;
+
+        if method == "initialize" {
+            ensure_legacy_initialize_info(&mut params, "clientInfo");
+        }
 
         if let Some(message) = try_convert_message_to_v2::<ClientRequest>(&method, &params)? {
             return Ok(message);
@@ -573,8 +577,12 @@ mod imp {
 
     fn public_to_v2_response(
         method: &str,
-        value: serde_json::Value,
+        mut value: serde_json::Value,
     ) -> Result<serde_json::Value, crate::Error> {
+        if method == "initialize" {
+            ensure_legacy_initialize_info(&mut value, "agentInfo");
+        }
+
         if let Some(value) = try_convert_response_to_v2::<AgentResponse>(method, &value)? {
             return Ok(value);
         }
@@ -585,6 +593,27 @@ mod imp {
         Ok(value)
     }
 
+    fn ensure_legacy_initialize_info(value: &mut serde_json::Value, field: &str) {
+        let serde_json::Value::Object(object) = value else {
+            return;
+        };
+
+        let needs_default = match object.get(field) {
+            Some(value) => value.is_null(),
+            None => true,
+        };
+
+        if needs_default {
+            object.insert(
+                field.into(),
+                serde_json::json!({
+                    "name": "legacy-acp-peer",
+                    "version": "unknown",
+                }),
+            );
+        }
+    }
+
     fn v2_to_public_response(
         method: &str,
         value: serde_json::Value,
@@ -728,6 +757,10 @@ mod imp {
                 .negotiated
         }
 
+        fn v2_implementation() -> v2::Implementation {
+            v2::Implementation::new("rust-sdk-test", "0.0.0")
+        }
+
         #[test]
         fn initialize_request_sets_active_wire_version_before_response() -> Result<(), crate::Error>
         {
@@ -736,7 +769,7 @@ mod imp {
 
             compat.incoming_message(UntypedMessage::new(
                 "initialize",
-                v2::InitializeRequest::new(ProtocolVersion::V2),
+                v2::InitializeRequest::new(ProtocolVersion::V2, v2_implementation()),
             )?)?;
 
             assert_eq!(negotiated(&compat), ProtocolVersionKind::V1);
@@ -746,6 +779,7 @@ mod imp {
                 "initialize",
                 Ok(serde_json::to_value(v2::InitializeResponse::new(
                     ProtocolVersion::V2,
+                    v2_implementation(),
                 ))?),
             )?;
 
@@ -762,7 +796,7 @@ mod imp {
 
             compat.outgoing_message(UntypedMessage::new(
                 "initialize",
-                v2::InitializeRequest::new(ProtocolVersion::V1),
+                v2::InitializeRequest::new(ProtocolVersion::V1, v2_implementation()),
             )?)?;
 
             assert_eq!(negotiated(&compat), ProtocolVersionKind::V1);
@@ -772,6 +806,7 @@ mod imp {
                 "initialize",
                 Ok(serde_json::to_value(v2::InitializeResponse::new(
                     ProtocolVersion::V2,
+                    v2_implementation(),
                 ))?),
             )?;
 
@@ -788,7 +823,7 @@ mod imp {
 
             compat.outgoing_message(UntypedMessage::new(
                 "initialize",
-                v2::InitializeRequest::new(ProtocolVersion::V1),
+                v2::InitializeRequest::new(ProtocolVersion::V1, v2_implementation()),
             )?)?;
 
             assert_eq!(negotiated(&compat), ProtocolVersionKind::V1);
@@ -814,7 +849,7 @@ mod imp {
                 let compat = ProtocolCompat::new(ProtocolMode::v2_client());
                 compat.outgoing_message(UntypedMessage::new(
                     "initialize",
-                    v2::InitializeRequest::new(ProtocolVersion::V1),
+                    v2::InitializeRequest::new(ProtocolVersion::V1, v2_implementation()),
                 )?)?;
 
                 let error = compat
@@ -838,7 +873,7 @@ mod imp {
             let compat = ProtocolCompat::new(ProtocolMode::v2_agent());
             let messages = compat.outgoing_notification(UntypedMessage::new(
                 "session/update",
-                v2::SessionNotification::new(
+                v2::UpdateSessionNotification::new(
                     "sess",
                     v2::SessionUpdate::AgentMessage(v2::AgentMessage::new("msg_agent").content(
                         vec![

src/agent-client-protocol/src/schema/client_to_agent/requests.rs

@@ -5,6 +5,7 @@ use crate::schema::v1::{
     LogoutRequest, LogoutResponse, NewSessionRequest, NewSessionResponse, PromptRequest,
     PromptResponse, ResumeSessionRequest, ResumeSessionResponse, SetSessionConfigOptionRequest,
     SetSessionConfigOptionResponse, SetSessionModeRequest, SetSessionModeResponse,
+    SetSessionTitleRequest, SetSessionTitleResponse,
 };
 #[cfg(feature = "unstable_session_fork")]
 use crate::schema::v1::{ForkSessionRequest, ForkSessionResponse};
@@ -31,6 +32,11 @@ impl_jsonrpc_request!(
     SetSessionConfigOptionResponse,
     "session/set_config_option"
 );
+impl_jsonrpc_request!(
+    SetSessionTitleRequest,
+    SetSessionTitleResponse,
+    "session/setTitle"
+);
 
 #[cfg(feature = "unstable_session_fork")]
 impl_jsonrpc_request!(ForkSessionRequest, ForkSessionResponse, "session/fork");

src/agent-client-protocol/src/schema/enum_impls.rs

@@ -24,6 +24,7 @@ impl_jsonrpc_request_enum!(ClientRequest {
     CloseSessionRequest => "session/close",
     SetSessionModeRequest => "session/set_mode",
     SetSessionConfigOptionRequest => "session/set_config_option",
+    SetSessionTitleRequest => "session/setTitle",
     PromptRequest => "session/prompt",
     #[cfg(feature = "unstable_mcp_over_acp")]
     MessageMcpRequest => "mcp/message",