feat(acp): add unstable session delete support

Author: benbrandt

Cargo.lock

@@ -30,7 +30,7 @@ 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 = "=0.13.0", features = ["tracing"] }
+agent-client-protocol-schema = { version = "=0.13.1", features = ["tracing"] }
 
 # Core async runtime
 tokio = { version = "1.52", features = ["full"] }

Cargo.toml

@@ -9,6 +9,7 @@
 
 ### Added
 
+- *(unstable)* Add support for `session/delete` method.
 - `McpConnectionTo::acp_id()` method.
 
 ### Deprecated

src/agent-client-protocol/CHANGELOG.md

@@ -22,6 +22,7 @@ unstable = [
     "unstable_mcp_over_acp",
     "unstable_message_id",
     "unstable_session_additional_directories",
+    "unstable_session_delete",
     "unstable_session_fork",
     "unstable_session_model",
     "unstable_session_usage",
@@ -32,6 +33,7 @@ unstable_logout = ["agent-client-protocol-schema/unstable_logout"]
 unstable_mcp_over_acp = ["agent-client-protocol-schema/unstable_mcp_over_acp"]
 unstable_message_id = ["agent-client-protocol-schema/unstable_message_id"]
 unstable_session_additional_directories = ["agent-client-protocol-schema/unstable_session_additional_directories"]
+unstable_session_delete = ["agent-client-protocol-schema/unstable_session_delete"]
 unstable_session_fork = ["agent-client-protocol-schema/unstable_session_fork"]
 unstable_session_model = ["agent-client-protocol-schema/unstable_session_model"]
 unstable_session_usage = ["agent-client-protocol-schema/unstable_session_usage"]

src/agent-client-protocol/Cargo.toml

@@ -5,6 +5,8 @@ use crate::schema::{
     PromptResponse, ResumeSessionRequest, ResumeSessionResponse, SetSessionConfigOptionRequest,
     SetSessionConfigOptionResponse, SetSessionModeRequest, SetSessionModeResponse,
 };
+#[cfg(feature = "unstable_session_delete")]
+use crate::schema::{DeleteSessionRequest, DeleteSessionResponse};
 #[cfg(feature = "unstable_session_fork")]
 use crate::schema::{ForkSessionRequest, ForkSessionResponse};
 #[cfg(feature = "unstable_logout")]
@@ -18,6 +20,12 @@ impl_jsonrpc_request!(AuthenticateRequest, AuthenticateResponse, "authenticate")
 impl_jsonrpc_request!(LogoutRequest, LogoutResponse, "logout");
 impl_jsonrpc_request!(LoadSessionRequest, LoadSessionResponse, "session/load");
 impl_jsonrpc_request!(ListSessionsRequest, ListSessionsResponse, "session/list");
+#[cfg(feature = "unstable_session_delete")]
+impl_jsonrpc_request!(
+    DeleteSessionRequest,
+    DeleteSessionResponse,
+    "session/delete"
+);
 impl_jsonrpc_request!(NewSessionRequest, NewSessionResponse, "session/new");
 impl_jsonrpc_request!(PromptRequest, PromptResponse, "session/prompt");
 impl_jsonrpc_request!(

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

@@ -15,6 +15,8 @@ impl_jsonrpc_request_enum!(ClientRequest {
     NewSessionRequest => "session/new",
     LoadSessionRequest => "session/load",
     ListSessionsRequest => "session/list",
+    #[cfg(feature = "unstable_session_delete")]
+    DeleteSessionRequest => "session/delete",
     #[cfg(feature = "unstable_session_fork")]
     ForkSessionRequest => "session/fork",
     ResumeSessionRequest => "session/resume",

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

@@ -0,0 +1,53 @@
+#![cfg(feature = "unstable_session_delete")]
+
+use agent_client_protocol::schema::{ClientRequest, DeleteSessionRequest, DeleteSessionResponse};
+use agent_client_protocol::{JsonRpcMessage, JsonRpcRequest, JsonRpcResponse};
+use serde_json::json;
+
+fn assert_request_response_pair<T: JsonRpcRequest<Response = DeleteSessionResponse>>() {}
+
+#[test]
+fn delete_session_request_has_jsonrpc_metadata() {
+    let request = DeleteSessionRequest::new("sess_abc123");
+
+    assert_eq!(request.method(), "session/delete");
+    assert!(DeleteSessionRequest::matches_method("session/delete"));
+    assert!(!DeleteSessionRequest::matches_method("session/close"));
+
+    let untyped = request.to_untyped_message().unwrap();
+    assert_eq!(untyped.method, "session/delete");
+    assert_eq!(untyped.params, json!({ "sessionId": "sess_abc123" }));
+
+    let parsed = DeleteSessionRequest::parse_message(
+        "session/delete",
+        &json!({ "sessionId": "sess_abc123" }),
+    )
+    .unwrap();
+    assert_eq!(parsed.session_id.0.as_ref(), "sess_abc123");
+}
+
+#[test]
+fn delete_session_participates_in_client_request_enum() {
+    let request = ClientRequest::DeleteSessionRequest(DeleteSessionRequest::new("sess_abc123"));
+
+    assert_eq!(request.method(), "session/delete");
+    assert!(ClientRequest::matches_method("session/delete"));
+
+    let parsed =
+        ClientRequest::parse_message("session/delete", &json!({ "sessionId": "sess_abc123" }))
+            .unwrap();
+    assert!(matches!(parsed, ClientRequest::DeleteSessionRequest(_)));
+}
+
+#[test]
+fn delete_session_response_round_trips_json() {
+    let value = DeleteSessionResponse::new()
+        .into_json("session/delete")
+        .unwrap();
+    assert_eq!(value, json!({}));
+
+    let parsed = DeleteSessionResponse::from_value("session/delete", value).unwrap();
+    assert_eq!(parsed, DeleteSessionResponse::new());
+
+    assert_request_response_pair::<DeleteSessionRequest>();
+}