feat(core): add reload_plugins tool

codex-rs/core/src/tools/handlers/mod.rs

@@ -15,6 +15,8 @@ pub(crate) mod multi_agents_spec;
 pub(crate) mod multi_agents_v2;
 mod plan;
 pub(crate) mod plan_spec;
+mod reload_plugins;
+pub(crate) mod reload_plugins_spec;
 mod request_permissions;
 mod request_plugin_install;
 pub(crate) mod request_plugin_install_spec;
@@ -59,6 +61,7 @@ pub use mcp_resource::ListMcpResourceTemplatesHandler;
 pub use mcp_resource::ListMcpResourcesHandler;
 pub use mcp_resource::ReadMcpResourceHandler;
 pub use plan::PlanHandler;
+pub use reload_plugins::ReloadPluginsHandler;
 pub use request_permissions::RequestPermissionsHandler;
 pub use request_plugin_install::RequestPluginInstallHandler;
 pub use request_user_input::RequestUserInputHandler;

codex-rs/core/src/tools/handlers/reload_plugins.rs

@@ -0,0 +1,70 @@
+use crate::function_tool::FunctionCallError;
+use crate::tools::context::FunctionToolOutput;
+use crate::tools::context::ToolInvocation;
+use crate::tools::context::ToolOutput;
+use crate::tools::context::ToolPayload;
+use crate::tools::context::boxed_tool_output;
+use crate::tools::handlers::reload_plugins_spec::RELOAD_PLUGINS_TOOL_NAME;
+use crate::tools::handlers::reload_plugins_spec::create_reload_plugins_tool;
+use crate::tools::registry::CoreToolRuntime;
+use crate::tools::registry::ToolExecutor;
+use codex_tools::ToolName;
+use codex_tools::ToolSpec;
+
+pub struct ReloadPluginsHandler;
+
+#[async_trait::async_trait]
+impl ToolExecutor<ToolInvocation> for ReloadPluginsHandler {
+    fn tool_name(&self) -> ToolName {
+        ToolName::plain(RELOAD_PLUGINS_TOOL_NAME)
+    }
+
+    fn spec(&self) -> Option<ToolSpec> {
+        Some(create_reload_plugins_tool())
+    }
+
+    async fn handle(
+        &self,
+        invocation: ToolInvocation,
+    ) -> Result<Box<dyn ToolOutput>, FunctionCallError> {
+        let ToolInvocation {
+            payload,
+            session,
+            turn,
+            ..
+        } = invocation;
+
+        match payload {
+            ToolPayload::Function { arguments } if arguments.trim() == "{}" => {}
+            ToolPayload::Function { arguments } if arguments.trim().is_empty() => {}
+            ToolPayload::Function { .. } => {
+                return Err(FunctionCallError::RespondToModel(
+                    "reload_plugins does not accept arguments".to_string(),
+                ));
+            }
+            _ => {
+                return Err(FunctionCallError::Fatal(format!(
+                    "{RELOAD_PLUGINS_TOOL_NAME} handler received unsupported payload"
+                )));
+            }
+        }
+
+        session.reload_user_config_layer().await;
+        let config = session.get_config().await;
+        session
+            .refresh_mcp_servers_now(
+                turn.as_ref(),
+                config.mcp_servers.get().clone(),
+                config.mcp_oauth_credentials_store_mode,
+                Some(session.mcp_elicitation_reviewer()),
+            )
+            .await;
+
+        Ok(boxed_tool_output(FunctionToolOutput::from_text(
+            "{\"reloaded\":true}".to_string(),
+            Some(true),
+        )))
+    }
+}
+
+impl CoreToolRuntime for ReloadPluginsHandler {}

codex-rs/core/src/tools/handlers/reload_plugins_spec.rs

@@ -0,0 +1,33 @@
+use codex_tools::JsonSchema;
+use codex_tools::ResponsesApiTool;
+use codex_tools::ToolSpec;
+use std::collections::BTreeMap;
+
+pub const RELOAD_PLUGINS_TOOL_NAME: &str = "reload_plugins";
+
+pub fn create_reload_plugins_tool() -> ToolSpec {
+    ToolSpec::Function(ResponsesApiTool {
+        name: RELOAD_PLUGINS_TOOL_NAME.to_string(),
+        description: "Reload plugin configuration, clear plugin and skill caches, and rebuild MCP tools from the refreshed plugin state.".to_string(),
+        strict: false,
+        defer_loading: None,
+        parameters: JsonSchema::object(BTreeMap::new(), Some(Vec::new()), Some(false.into())),
+        output_schema: None,
+    })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn reload_plugins_tool_has_no_arguments() {
+        let ToolSpec::Function(tool) = create_reload_plugins_tool() else {
+            panic!("reload_plugins should be a function tool");
+        };
+
+        assert_eq!(tool.name, RELOAD_PLUGINS_TOOL_NAME);
+        assert_eq!(tool.parameters.required, Some(Vec::new()));
+        assert_eq!(tool.parameters.properties, Some(BTreeMap::new()));
+    }
+}

codex-rs/core/src/tools/spec_plan.rs

@@ -16,6 +16,7 @@ use crate::tools::handlers::ListMcpResourcesHandler;
 use crate::tools::handlers::McpHandler;
 use crate::tools::handlers::PlanHandler;
 use crate::tools::handlers::ReadMcpResourceHandler;
+use crate::tools::handlers::ReloadPluginsHandler;
 use crate::tools::handlers::RequestPermissionsHandler;
 use crate::tools::handlers::RequestPluginInstallHandler;
 use crate::tools::handlers::RequestUserInputHandler;
@@ -45,6 +46,7 @@ use crate::tools::handlers::multi_agents_v2::ListAgentsHandler as ListAgentsHand
 use crate::tools::handlers::multi_agents_v2::SendMessageHandler as SendMessageHandlerV2;
 use crate::tools::handlers::multi_agents_v2::SpawnAgentHandler as SpawnAgentHandlerV2;
 use crate::tools::handlers::multi_agents_v2::WaitAgentHandler as WaitAgentHandlerV2;
+use crate::tools::handlers::reload_plugins_spec::RELOAD_PLUGINS_TOOL_NAME;
 use crate::tools::handlers::view_image_spec::ViewImageToolOptions;
 use crate::tools::hosted_spec::WebSearchToolOptions;
 use crate::tools::hosted_spec::create_image_generation_tool;
@@ -435,6 +437,14 @@ fn collect_tool_executors(
         executors.push(Arc::new(TestSyncHandler));
     }
 
+    if config
+        .experimental_supported_tools
+        .iter()
+        .any(|tool| tool == RELOAD_PLUGINS_TOOL_NAME)
+    {
+        executors.push(Arc::new(ReloadPluginsHandler));
+    }
+
     if config.environment_mode.has_environment() {
         let include_environment_id =
             matches!(config.environment_mode, ToolEnvironmentMode::Multiple);

codex-rs/core/src/tools/spec_plan_tests.rs

@@ -14,6 +14,7 @@ use crate::tools::handlers::multi_agents_spec::create_spawn_agent_tool_v2;
 use crate::tools::handlers::multi_agents_spec::create_wait_agent_tool_v1;
 use crate::tools::handlers::multi_agents_spec::create_wait_agent_tool_v2;
 use crate::tools::handlers::plan_spec::create_update_plan_tool;
+use crate::tools::handlers::reload_plugins_spec::RELOAD_PLUGINS_TOOL_NAME;
 use crate::tools::handlers::request_user_input_spec::REQUEST_USER_INPUT_TOOL_NAME;
 use crate::tools::handlers::request_user_input_spec::create_request_user_input_tool;
 use crate::tools::handlers::request_user_input_spec::request_user_input_tool_description;
@@ -1392,6 +1393,36 @@ fn test_test_model_info_includes_sync_tool() {
     assert!(tools.iter().any(|tool| tool.name() == "test_sync_tool"));
 }
 
+#[test]
+fn test_model_info_includes_reload_plugins_tool() {
+    let mut model_info = model_info();
+    model_info.experimental_supported_tools = vec![RELOAD_PLUGINS_TOOL_NAME.to_string()];
+    let features = Features::with_defaults();
+    let available_models = Vec::new();
+    let tools_config = ToolsConfig::new(&ToolsConfigParams {
+        model_info: &model_info,
+        available_models: &available_models,
+        features: &features,
+        image_generation_tool_auth_allowed: true,
+        web_search_mode: Some(WebSearchMode::Cached),
+        session_source: SessionSource::Cli,
+        permission_profile: &PermissionProfile::Disabled,
+        windows_sandbox_level: WindowsSandboxLevel::Disabled,
+    });
+    let (tools, _) = build_specs(
+        &tools_config,
+        /*mcp_tools*/ None,
+        /*deferred_mcp_tools*/ None,
+        &[],
+    );
+
+    assert!(
+        tools
+            .iter()
+            .any(|tool| tool.name() == RELOAD_PLUGINS_TOOL_NAME)
+    );
+}
+
 #[test]
 fn test_build_specs_mcp_tools_converted() {
     let model_info = model_info();