Add Rust SDK model allowlist support

rust/src/generated/api_types.rs

@@ -296,6 +296,8 @@ pub mod rpc_methods {
     pub const SESSION_MODEL_SETREASONINGEFFORT: &str = "session.model.setReasoningEffort";
     /// `session.model.list`
     pub const SESSION_MODEL_LIST: &str = "session.model.list";
+    /// `session.model.setAllowedModels`
+    pub const SESSION_MODEL_SETALLOWEDMODELS: &str = "session.model.setAllowedModels";
     /// `session.mode.get`
     pub const SESSION_MODE_GET: &str = "session.mode.get";
     /// `session.mode.set`
@@ -22010,6 +22012,47 @@ pub struct WorkspacesWriteAutopilotObjectiveResult {
     pub operation: String,
 }
 
+/// Host-supplied exact CAPI model IDs to allow for this running session. The runtime intersects the list with repository `.github/allowed_models.txt` policy. Omit or pass null to clear the host restriction; an explicit empty or disjoint list is rejected.
+///
+/// <div class="warning">
+///
+/// **Experimental.** This type is part of an experimental wire-protocol surface
+/// and may change or be removed in future SDK or CLI releases.
+///
+/// </div>
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ModelSetAllowedModelsRequest {
+    /// Exact model IDs to permit, or null to clear the host restriction.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub allowed_models: Option<Vec<String>>,
+}
+
+/// The applied host allowlist and effective session model policy after intersection.
+///
+/// <div class="warning">
+///
+/// **Experimental.** This type is part of an experimental wire-protocol surface
+/// and may change or be removed in future SDK or CLI releases.
+///
+/// </div>
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ModelSetAllowedModelsResult {
+    /// Normalized host allowlist. Omitted when the host restriction was cleared.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub allowed_models: Option<Vec<String>>,
+    /// Effective exact IDs or repository policy patterns after applying the host restriction. Omitted by relay clients whose AHP host applies the policy asynchronously.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub effective_allowed_models: Option<Vec<String>>,
+    /// Effective deterministic fallback model, when the policy defines one.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub fallback_model: Option<String>,
+    /// Selected session model after reconciling a now-disallowed concrete selection.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub model_id: Option<String>,
+}
+
 /// List of Copilot models available to the resolved user, including capabilities and billing metadata.
 ///
 /// <div class="warning">
@@ -23561,6 +23604,31 @@ pub struct SessionModelListResult {
     pub quota_snapshots: Option<HashMap<String, serde_json::Value>>,
 }
 
+/// The applied host allowlist and effective session model policy after intersection.
+///
+/// <div class="warning">
+///
+/// **Experimental.** This type is part of an experimental wire-protocol surface
+/// and may change or be removed in future SDK or CLI releases.
+///
+/// </div>
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct SessionModelSetAllowedModelsResult {
+    /// Normalized host allowlist. Omitted when the host restriction was cleared.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub allowed_models: Option<Vec<String>>,
+    /// Effective exact IDs or repository policy patterns after applying the host restriction. Omitted by relay clients whose AHP host applies the policy asynchronously.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub effective_allowed_models: Option<Vec<String>>,
+    /// Effective deterministic fallback model, when the policy defines one.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub fallback_model: Option<String>,
+    /// Selected session model after reconciling a now-disallowed concrete selection.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub model_id: Option<String>,
+}
+
 /// Identifies the target session.
 ///
 /// <div class="warning">

rust/src/generated/rpc.rs

@@ -7674,6 +7674,42 @@ impl<'a> SessionRpcModel<'a> {
             .await?;
         Ok(serde_json::from_value(_value)?)
     }
+
+    /// Replaces or clears the host-supplied model allowlist for a running session.
+    ///
+    /// Wire method: `session.model.setAllowedModels`.
+    ///
+    /// # Parameters
+    ///
+    /// * `params` - Host-supplied exact CAPI model IDs to allow for this running session. The runtime intersects the list with repository `.github/allowed_models.txt` policy. Omit or pass null to clear the host restriction; an explicit empty or disjoint list is rejected.
+    ///
+    /// # Returns
+    ///
+    /// The applied host allowlist and effective session model policy after intersection.
+    ///
+    /// <div class="warning">
+    ///
+    /// **Experimental.** This API is part of an experimental wire-protocol surface
+    /// and may change or be removed in future SDK or CLI releases. Pin both the
+    /// SDK and CLI versions if your code depends on it.
+    ///
+    /// </div>
+    pub async fn set_allowed_models(
+        &self,
+        params: ModelSetAllowedModelsRequest,
+    ) -> Result<ModelSetAllowedModelsResult, Error> {
+        let mut wire_params = serde_json::to_value(params)?;
+        wire_params["sessionId"] = serde_json::Value::String(self.session.id().to_string());
+        let _value = self
+            .session
+            .client()
+            .call(
+                rpc_methods::SESSION_MODEL_SETALLOWEDMODELS,
+                Some(wire_params),
+            )
+            .await?;
+        Ok(serde_json::from_value(_value)?)
+    }
 }
 
 /// `session.name.*` RPCs.

rust/src/types.rs

@@ -1939,6 +1939,11 @@ pub struct SessionConfig {
     pub session_id: Option<SessionId>,
     /// Model to use (e.g. `"gpt-4"`, `"claude-sonnet-4"`).
     pub model: Option<String>,
+    /// Exact model IDs this session may use. When unset, the host imposes no
+    /// model restriction. The runtime validates configured IDs, rejects an
+    /// explicit empty list, and intersects the list with applicable model
+    /// policies.
+    pub allowed_models: Option<Vec<String>>,
     /// Application name sent as `User-Agent` context.
     pub client_name: Option<String>,
     /// Reasoning effort level (e.g. `"low"`, `"medium"`, `"high"`).
@@ -2273,6 +2278,7 @@ impl std::fmt::Debug for SessionConfig {
         f.debug_struct("SessionConfig")
             .field("session_id", &self.session_id)
             .field("model", &self.model)
+            .field("allowed_models", &self.allowed_models)
             .field("client_name", &self.client_name)
             .field("reasoning_effort", &self.reasoning_effort)
             .field("reasoning_summary", &self.reasoning_summary)
@@ -2415,6 +2421,7 @@ impl Default for SessionConfig {
         Self {
             session_id: None,
             model: None,
+            allowed_models: None,
             client_name: None,
             reasoning_effort: None,
             reasoning_summary: None,
@@ -2584,6 +2591,7 @@ impl SessionConfig {
         let wire = crate::wire::SessionCreateWire {
             session_id,
             model: self.model,
+            allowed_models: self.allowed_models,
             client_name: self.client_name,
             reasoning_effort: self.reasoning_effort,
             reasoning_summary: self.reasoning_summary,
@@ -2807,6 +2815,19 @@ impl SessionConfig {
         self
     }
 
+    /// Restrict this session to the provided exact model IDs.
+    ///
+    /// Passing an empty iterator sends an explicit empty list, which the
+    /// runtime rejects.
+    pub fn with_allowed_models<I, S>(mut self, models: I) -> Self
+    where
+        I: IntoIterator<Item = S>,
+        S: Into<String>,
+    {
+        self.allowed_models = Some(models.into_iter().map(Into::into).collect());
+        self
+    }
+
     /// Set the application name sent as `User-Agent` context.
     pub fn with_client_name(mut self, name: impl Into<String>) -> Self {
         self.client_name = Some(name.into());
@@ -3347,6 +3368,11 @@ pub struct ResumeSessionConfig {
     /// Model to use for this session (e.g. `"gpt-4"`, `"claude-sonnet-4"`).
     /// Can change the model when resuming.
     pub model: Option<String>,
+    /// Exact model IDs the resumed session may use. When unset, the host
+    /// imposes no model restriction. The runtime validates configured IDs,
+    /// rejects an explicit empty list, and intersects the list with applicable
+    /// model policies.
+    pub allowed_models: Option<Vec<String>>,
     /// Application name sent as User-Agent context.
     pub client_name: Option<String>,
     /// Desired reasoning effort to apply after resuming the session.
@@ -3609,6 +3635,7 @@ impl std::fmt::Debug for ResumeSessionConfig {
         f.debug_struct("ResumeSessionConfig")
             .field("session_id", &self.session_id)
             .field("model", &self.model)
+            .field("allowed_models", &self.allowed_models)
             .field("client_name", &self.client_name)
             .field("reasoning_effort", &self.reasoning_effort)
             .field("reasoning_summary", &self.reasoning_summary)
@@ -3794,6 +3821,7 @@ impl ResumeSessionConfig {
         let wire = crate::wire::SessionResumeWire {
             session_id: self.session_id,
             model: self.model,
+            allowed_models: self.allowed_models,
             client_name: self.client_name,
             reasoning_effort: self.reasoning_effort,
             reasoning_summary: self.reasoning_summary,
@@ -3902,6 +3930,7 @@ impl ResumeSessionConfig {
         Self {
             session_id,
             model: None,
+            allowed_models: None,
             client_name: None,
             reasoning_effort: None,
             reasoning_summary: None,
@@ -4095,6 +4124,19 @@ impl ResumeSessionConfig {
         self
     }
 
+    /// Restrict the resumed session to the provided exact model IDs.
+    ///
+    /// Passing an empty iterator sends an explicit empty list, which the
+    /// runtime rejects.
+    pub fn with_allowed_models<I, S>(mut self, models: I) -> Self
+    where
+        I: IntoIterator<Item = S>,
+        S: Into<String>,
+    {
+        self.allowed_models = Some(models.into_iter().map(Into::into).collect());
+        self
+    }
+
     /// Set the application name sent as `User-Agent` context.
     pub fn with_client_name(mut self, name: impl Into<String>) -> Self {
         self.client_name = Some(name.into());
@@ -6312,6 +6354,7 @@ mod tests {
     fn session_config_default_wire_flags_off_without_handlers() {
         let cfg = SessionConfig::default();
         assert_eq!(cfg.mcp_oauth_token_storage, None);
+        assert_eq!(cfg.allowed_models, None);
         // Wire flags are derived from handler presence at create_session
         // time, not stored on the config. With no handlers installed, every
         // request_* flag should serialize as false.
@@ -6327,12 +6370,14 @@ mod tests {
         assert!(!wire.request_mcp_apps);
         let json = serde_json::to_value(&wire).unwrap();
         assert!(json.get("askUserVariant").is_none());
+        assert!(json.get("allowedModels").is_none());
     }
 
     #[test]
     fn resume_session_config_new_wire_flags_off_without_handlers() {
         let cfg = ResumeSessionConfig::new(SessionId::from("resume-flags"));
         assert_eq!(cfg.mcp_oauth_token_storage, None);
+        assert_eq!(cfg.allowed_models, None);
         let (wire, _runtime) = cfg
             .into_wire()
             .expect("default resume config has no duplicate handlers");
@@ -6345,6 +6390,43 @@ mod tests {
         assert!(!wire.request_mcp_apps);
         let json = serde_json::to_value(&wire).unwrap();
         assert!(json.get("askUserVariant").is_none());
+        assert!(json.get("allowedModels").is_none());
+    }
+
+    #[test]
+    fn session_configs_build_debug_and_serialize_allowed_models() {
+        let create = SessionConfig::default().with_allowed_models(["gpt-5.4", "claude-sonnet-4"]);
+        assert_eq!(
+            create.allowed_models.as_deref(),
+            Some(&["gpt-5.4".to_string(), "claude-sonnet-4".to_string()][..])
+        );
+        assert!(format!("{create:?}").contains("allowed_models"));
+
+        let (create_wire, _) = create
+            .into_wire(Some(SessionId::from("create-allowed-models")))
+            .expect("allowed model config has no duplicate handlers");
+        let create_json = serde_json::to_value(&create_wire).unwrap();
+        assert_eq!(
+            create_json["allowedModels"],
+            json!(["gpt-5.4", "claude-sonnet-4"])
+        );
+
+        let resume = ResumeSessionConfig::new(SessionId::from("resume-allowed-models"))
+            .with_allowed_models(vec!["gpt-5.4".to_string(), "gpt-5-mini".to_string()]);
+        assert_eq!(
+            resume.allowed_models.as_deref(),
+            Some(&["gpt-5.4".to_string(), "gpt-5-mini".to_string()][..])
+        );
+        assert!(format!("{resume:?}").contains("allowed_models"));
+
+        let (resume_wire, _) = resume
+            .into_wire()
+            .expect("resume allowed model config has no duplicate handlers");
+        let resume_json = serde_json::to_value(&resume_wire).unwrap();
+        assert_eq!(
+            resume_json["allowedModels"],
+            json!(["gpt-5.4", "gpt-5-mini"])
+        );
     }
 
     #[test]

rust/src/wire.rs

@@ -53,6 +53,8 @@ pub(crate) struct SessionCreateWire {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub model: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
+    pub allowed_models: Option<Vec<String>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub client_name: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub reasoning_effort: Option<String>,
@@ -211,6 +213,8 @@ pub(crate) struct SessionResumeWire {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub model: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
+    pub allowed_models: Option<Vec<String>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub client_name: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub reasoning_effort: Option<String>,

rust/tests/api_types_test.rs

@@ -6,8 +6,9 @@
 use github_copilot_sdk::AutoTier;
 use github_copilot_sdk::rpc::{
     Extension, ExtensionList, ExtensionSource, ExtensionStatus, ExtensionsDisableRequest,
-    ExtensionsEnableRequest, FleetStartRequest, FleetStartResult, QueuePendingItems,
-    QueuePendingItemsKind, SendAgentMode, TasksStartAgentRequest,
+    ExtensionsEnableRequest, FleetStartRequest, FleetStartResult, ModelSetAllowedModelsRequest,
+    ModelSetAllowedModelsResult, QueuePendingItems, QueuePendingItemsKind, SendAgentMode,
+    TasksStartAgentRequest,
 };
 use github_copilot_sdk::session_events::{
     PermissionRequest, PermissionRequestedData, SessionEventData, TypedSessionEvent,
@@ -128,6 +129,42 @@ fn tasks_start_agent_request_fields_are_accessible() {
     assert_eq!(request.description.as_deref(), Some("SDK task agent"));
 }
 
+#[test]
+fn model_allowed_models_request_and_result_preserve_contract_fields() {
+    let replace = ModelSetAllowedModelsRequest {
+        allowed_models: Some(vec!["gpt-5.4".to_string(), "gpt-5-mini".to_string()]),
+    };
+    assert_eq!(
+        serde_json::to_value(&replace).unwrap(),
+        serde_json::json!({ "allowedModels": ["gpt-5.4", "gpt-5-mini"] })
+    );
+
+    let clear = ModelSetAllowedModelsRequest::default();
+    assert_eq!(clear.allowed_models, None);
+    assert_eq!(serde_json::to_value(&clear).unwrap(), serde_json::json!({}));
+
+    let explicit_null: ModelSetAllowedModelsRequest =
+        serde_json::from_value(serde_json::json!({ "allowedModels": null })).unwrap();
+    assert_eq!(explicit_null.allowed_models, None);
+
+    let result = ModelSetAllowedModelsResult {
+        allowed_models: Some(vec!["gpt-5.4".to_string()]),
+        effective_allowed_models: Some(vec!["gpt-5.4".to_string()]),
+        fallback_model: Some("gpt-5.4".to_string()),
+        model_id: Some("gpt-5.4".to_string()),
+    };
+    assert_eq!(
+        result.allowed_models.as_deref(),
+        Some(["gpt-5.4".to_string()].as_slice())
+    );
+    assert_eq!(
+        result.effective_allowed_models.as_deref(),
+        Some(["gpt-5.4".to_string()].as_slice())
+    );
+    assert_eq!(result.fallback_model.as_deref(), Some("gpt-5.4"));
+    assert_eq!(result.model_id.as_deref(), Some("gpt-5.4"));
+}
+
 #[test]
 fn permission_event_exposes_managed_approval_required() {
     let data: PermissionRequestedData = serde_json::from_value(serde_json::json!({