SDK: add optional memory configuration to session create and resume

rust/README.md

@@ -565,6 +565,18 @@ config.infinite_sessions = Some(infinite);
 
 The CLI emits `session.compaction_start` / `session.compaction_complete` events around each compaction. The session id remains stable across compactions; resume with `Client::resume_session` to pick up a prior conversation. Workspace state lives under `~/.copilot/session-state/{sessionId}` by default — override with `workspace_path` to relocate.
 
+### Memory
+
+Configure the runtime memory feature for a session:
+
+```rust,ignore
+use github_copilot_sdk::types::MemoryConfiguration;
+
+let config = SessionConfig::default().with_memory(MemoryConfiguration::enabled());
+```
+
+`MemoryConfiguration` is accepted on both `Client::create_session` and `Client::resume_session` (via `ResumeSessionConfig::with_memory`). `enabled` toggles the feature.
+
 ### Custom Providers (BYOK)
 
 Route model traffic through your own inference endpoint instead of GitHub's hosted models:

rust/src/types.rs

@@ -776,6 +776,42 @@ impl InfiniteSessionConfig {
     }
 }
 
+/// Per-session configuration for the runtime memory feature.
+///
+/// Supplied via [`SessionConfig::with_memory`] /
+/// [`ResumeSessionConfig::with_memory`]. When a session is created or resumed
+/// without a memory configuration, the runtime applies its own default for the
+/// memory feature.
+///
+/// The type is extensible: today it carries [`enabled`](Self::enabled), and
+/// further tuning knobs can be added as optional fields without a breaking
+/// change.
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(rename_all = "camelCase")]
+#[non_exhaustive]
+pub struct MemoryConfiguration {
+    /// Whether the memory feature is enabled for this session.
+    pub enabled: bool,
+}
+
+impl MemoryConfiguration {
+    /// A configuration with the memory feature enabled.
+    pub fn enabled() -> Self {
+        Self { enabled: true }
+    }
+
+    /// A configuration with the memory feature disabled.
+    pub fn disabled() -> Self {
+        Self { enabled: false }
+    }
+
+    /// Set whether the memory feature is enabled.
+    pub fn with_enabled(mut self, enabled: bool) -> Self {
+        self.enabled = enabled;
+        self
+    }
+}
+
 /// GitHub repository metadata to associate with a cloud session.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
@@ -1289,6 +1325,8 @@ pub struct SessionConfig {
     /// Per-property overrides for model capabilities, deep-merged over
     /// runtime defaults.
     pub model_capabilities: Option<crate::generated::api_types::ModelCapabilitiesOverride>,
+    /// Per-session configuration for the runtime memory feature.
+    pub memory: Option<MemoryConfiguration>,
     /// Override the default configuration directory location. When set,
     /// the session uses this directory for storing config and state.
     pub config_directory: Option<PathBuf>,
@@ -1431,6 +1469,7 @@ impl std::fmt::Debug for SessionConfig {
             .field("provider", &self.provider)
             .field("enable_session_telemetry", &self.enable_session_telemetry)
             .field("model_capabilities", &self.model_capabilities)
+            .field("memory", &self.memory)
             .field("config_directory", &self.config_directory)
             .field("working_directory", &self.working_directory)
             .field(
@@ -1530,6 +1569,7 @@ impl Default for SessionConfig {
             provider: None,
             enable_session_telemetry: None,
             model_capabilities: None,
+            memory: None,
             config_directory: None,
             working_directory: None,
             github_token: None,
@@ -1672,6 +1712,7 @@ impl SessionConfig {
             provider: self.provider,
             enable_session_telemetry: self.enable_session_telemetry,
             model_capabilities: self.model_capabilities,
+            memory: self.memory,
             config_dir: self.config_directory,
             working_directory: self.working_directory,
             github_token: self.github_token,
@@ -2103,6 +2144,12 @@ impl SessionConfig {
         self
     }
 
+    /// Configure the runtime memory feature for this session.
+    pub fn with_memory(mut self, memory: MemoryConfiguration) -> Self {
+        self.memory = Some(memory);
+        self
+    }
+
     /// Override the default configuration directory location.
     pub fn with_config_directory(mut self, dir: impl Into<PathBuf>) -> Self {
         self.config_directory = Some(dir.into());
@@ -2285,6 +2332,8 @@ pub struct ResumeSessionConfig {
     pub enable_session_telemetry: Option<bool>,
     /// Per-property model capability overrides on resume.
     pub model_capabilities: Option<crate::generated::api_types::ModelCapabilitiesOverride>,
+    /// Per-session configuration for the runtime memory feature on resume.
+    pub memory: Option<MemoryConfiguration>,
     /// Override the default configuration directory location on resume.
     pub config_directory: Option<PathBuf>,
     /// Per-session working directory on resume.
@@ -2408,6 +2457,7 @@ impl std::fmt::Debug for ResumeSessionConfig {
             .field("provider", &self.provider)
             .field("enable_session_telemetry", &self.enable_session_telemetry)
             .field("model_capabilities", &self.model_capabilities)
+            .field("memory", &self.memory)
             .field("config_directory", &self.config_directory)
             .field("working_directory", &self.working_directory)
             .field(
@@ -2551,6 +2601,7 @@ impl ResumeSessionConfig {
             provider: self.provider,
             enable_session_telemetry: self.enable_session_telemetry,
             model_capabilities: self.model_capabilities,
+            memory: self.memory,
             config_dir: self.config_directory,
             working_directory: self.working_directory,
             github_token: self.github_token,
@@ -2627,6 +2678,7 @@ impl ResumeSessionConfig {
             provider: None,
             enable_session_telemetry: None,
             model_capabilities: None,
+            memory: None,
             config_directory: None,
             working_directory: None,
             github_token: None,
@@ -3031,6 +3083,12 @@ impl ResumeSessionConfig {
         self
     }
 
+    /// Configure the runtime memory feature for the resumed session.
+    pub fn with_memory(mut self, memory: MemoryConfiguration) -> Self {
+        self.memory = Some(memory);
+        self
+    }
+
     /// Override the default configuration directory location on resume.
     pub fn with_config_directory(mut self, dir: impl Into<PathBuf>) -> Self {
         self.config_directory = Some(dir.into());
@@ -4271,9 +4329,9 @@ mod tests {
     use super::{
         AgentMode, Attachment, AttachmentLineRange, AttachmentSelectionPosition,
         AttachmentSelectionRange, ConnectionState, CustomAgentConfig, DeliveryMode, ExtensionInfo,
-        GitHubReferenceType, InfiniteSessionConfig, LargeToolOutputConfig, ProviderConfig,
-        ReasoningSummary, ResumeSessionConfig, SessionConfig, SessionEvent, SessionId,
-        SystemMessageConfig, Tool, ToolBinaryResult, ToolResult, ToolResultExpanded,
+        GitHubReferenceType, InfiniteSessionConfig, LargeToolOutputConfig, MemoryConfiguration,
+        ProviderConfig, ReasoningSummary, ResumeSessionConfig, SessionConfig, SessionEvent,
+        SessionId, SystemMessageConfig, Tool, ToolBinaryResult, ToolResult, ToolResultExpanded,
         ToolResultResponse, ensure_attachment_display_names,
     };
     use crate::generated::session_events::TypedSessionEvent;
@@ -4453,6 +4511,57 @@ mod tests {
         assert_eq!(json["requestMcpApps"], serde_json::Value::Bool(true));
     }
 
+    #[test]
+    fn memory_configuration_constructors_and_serde() {
+        assert!(MemoryConfiguration::enabled().enabled);
+        assert!(!MemoryConfiguration::disabled().enabled);
+        assert!(MemoryConfiguration::disabled().with_enabled(true).enabled);
+
+        let json = serde_json::to_value(MemoryConfiguration::enabled()).unwrap();
+        assert_eq!(json, serde_json::json!({ "enabled": true }));
+    }
+
+    #[test]
+    fn session_config_with_memory_serializes() {
+        let (wire, _runtime) = SessionConfig::default()
+            .with_memory(MemoryConfiguration::enabled())
+            .into_wire(Some(SessionId::from("memory-on")))
+            .expect("no duplicate handlers");
+        let json = serde_json::to_value(&wire).unwrap();
+        assert_eq!(json["memory"], serde_json::json!({ "enabled": true }));
+
+        let (wire_off, _) = SessionConfig::default()
+            .with_memory(MemoryConfiguration::disabled())
+            .into_wire(Some(SessionId::from("memory-off")))
+            .expect("no duplicate handlers");
+        let json_off = serde_json::to_value(&wire_off).unwrap();
+        assert_eq!(json_off["memory"], serde_json::json!({ "enabled": false }));
+
+        // Unset memory is omitted on the wire.
+        let (empty_wire, _) = SessionConfig::default()
+            .into_wire(Some(SessionId::from("memory-unset")))
+            .expect("no duplicate handlers");
+        let empty_json = serde_json::to_value(&empty_wire).unwrap();
+        assert!(empty_json.get("memory").is_none());
+    }
+
+    #[test]
+    fn resume_session_config_with_memory_serializes() {
+        let (wire, _runtime) = ResumeSessionConfig::new(SessionId::from("resume-memory-on"))
+            .with_memory(MemoryConfiguration::enabled())
+            .into_wire()
+            .expect("no duplicate handlers");
+        let json = serde_json::to_value(&wire).unwrap();
+        assert_eq!(json["memory"], serde_json::json!({ "enabled": true }));
+
+        // Unset memory is omitted on the wire.
+        let (empty_wire, _) = ResumeSessionConfig::new(SessionId::from("resume-memory-unset"))
+            .into_wire()
+            .expect("no duplicate handlers");
+        let empty_json = serde_json::to_value(&empty_wire).unwrap();
+        assert!(empty_json.get("memory").is_none());
+    }
+
     #[test]
     #[allow(clippy::field_reassign_with_default)]
     fn session_config_into_wire_serializes_bucket_b_fields() {

rust/src/wire.rs

@@ -25,8 +25,8 @@ use crate::generated::api_types::{
 use crate::generated::session_events::ReasoningSummary;
 use crate::types::{
     CloudSessionOptions, CustomAgentConfig, DefaultAgentConfig, ExtensionInfo,
-    InfiniteSessionConfig, LargeToolOutputConfig, McpServerConfig, ProviderConfig, SessionId,
-    SystemMessageConfig, Tool,
+    InfiniteSessionConfig, LargeToolOutputConfig, McpServerConfig, MemoryConfiguration,
+    ProviderConfig, SessionId, SystemMessageConfig, Tool,
 };
 
 /// Wire representation of a slash command (name + description only). The
@@ -134,6 +134,8 @@ pub(crate) struct SessionCreateWire {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub model_capabilities: Option<ModelCapabilitiesOverride>,
     #[serde(skip_serializing_if = "Option::is_none")]
+    pub memory: Option<MemoryConfiguration>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub config_dir: Option<PathBuf>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub working_directory: Option<PathBuf>,
@@ -241,6 +243,8 @@ pub(crate) struct SessionResumeWire {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub model_capabilities: Option<ModelCapabilitiesOverride>,
     #[serde(skip_serializing_if = "Option::is_none")]
+    pub memory: Option<MemoryConfiguration>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub config_dir: Option<PathBuf>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub working_directory: Option<PathBuf>,