[plugins] Install MCPs when calling plugin/install (#15195)

- [x] Auth MCPs when installing plugins.

codex-rs/app-server/README.md

@@ -168,7 +168,7 @@ Example with notification opt-out:
 - `skills/changed` — notification emitted when watched local skill files change.
 - `app/list` — list available apps.
 - `skills/config/write` — write user-level skill config by path.
-- `plugin/install` — install a plugin from a discovered marketplace entry, rejecting marketplace entries marked unavailable for install, and return the effective plugin auth policy plus any apps that still need auth (**under development; do not call from production clients yet**).
+- `plugin/install` — install a plugin from a discovered marketplace entry, rejecting marketplace entries marked unavailable for install, install MCPs if any, and return the effective plugin auth policy plus any apps that still need auth (**under development; do not call from production clients yet**).
 - `plugin/uninstall` — uninstall a plugin by id by removing its cached files and clearing its user-level config entry (**under development; do not call from production clients yet**).
 - `mcpServer/oauth/login` — start an OAuth login for a configured MCP server; returns an `authorization_url` and later emits `mcpServer/oauthLogin/completed` once the browser flow finishes.
 - `tool/requestUserInput` — prompt the user with 1–3 short questions for a tool call and return their answers (experimental).

codex-rs/app-server/src/codex_message_processor.rs

@@ -228,6 +228,7 @@ use codex_core::plugins::PluginInstallRequest;
 use codex_core::plugins::PluginReadRequest;
 use codex_core::plugins::PluginUninstallError as CorePluginUninstallError;
 use codex_core::plugins::load_plugin_apps;
+use codex_core::plugins::load_plugin_mcp_servers;
 use codex_core::read_head_for_summary;
 use codex_core::read_session_meta_line;
 use codex_core::rollout_date_parts;
@@ -311,6 +312,7 @@ use codex_app_server_protocol::ServerRequest;
 
 mod apps_list_helpers;
 mod plugin_app_helpers;
+mod plugin_mcp_oauth;
 
 use crate::filters::compute_source_filters;
 use crate::filters::source_kind_matches;
@@ -4587,20 +4589,28 @@ impl CodexMessageProcessor {
             }
         };
 
-        let configured_servers = self
-            .thread_manager
-            .mcp_manager()
-            .configured_servers(&config);
+        if let Err(error) = self.queue_mcp_server_refresh_for_config(&config).await {
+            self.outgoing.send_error(request_id, error).await;
+            return;
+        }
+
+        let response = McpServerRefreshResponse {};
+        self.outgoing.send_response(request_id, response).await;
+    }
+
+    async fn queue_mcp_server_refresh_for_config(
+        &self,
+        config: &Config,
+    ) -> Result<(), JSONRPCErrorError> {
+        let configured_servers = self.thread_manager.mcp_manager().configured_servers(config);
         let mcp_servers = match serde_json::to_value(configured_servers) {
             Ok(value) => value,
             Err(err) => {
-                let error = JSONRPCErrorError {
+                return Err(JSONRPCErrorError {
                     code: INTERNAL_ERROR_CODE,
                     message: format!("failed to serialize MCP servers: {err}"),
                     data: None,
-                };
-                self.outgoing.send_error(request_id, error).await;
-                return;
+                });
             }
         };
 
@@ -4608,15 +4618,13 @@ impl CodexMessageProcessor {
             match serde_json::to_value(config.mcp_oauth_credentials_store_mode) {
                 Ok(value) => value,
                 Err(err) => {
-                    let error = JSONRPCErrorError {
+                    return Err(JSONRPCErrorError {
                         code: INTERNAL_ERROR_CODE,
                         message: format!(
                             "failed to serialize MCP OAuth credentials store mode: {err}"
                         ),
                         data: None,
-                    };
-                    self.outgoing.send_error(request_id, error).await;
-                    return;
+                    });
                 }
             };
 
@@ -4629,8 +4637,7 @@ impl CodexMessageProcessor {
         // active turn to avoid work for threads that never resume.
         let thread_manager = Arc::clone(&self.thread_manager);
         thread_manager.refresh_mcp_servers(refresh_config).await;
-        let response = McpServerRefreshResponse {};
-        self.outgoing.send_response(request_id, response).await;
+        Ok(())
     }
 
     async fn mcp_server_oauth_login(
@@ -5742,6 +5749,22 @@ impl CodexMessageProcessor {
                         self.config.as_ref().clone()
                     }
                 };
+
+                self.clear_plugin_related_caches();
+
+                let plugin_mcp_servers = load_plugin_mcp_servers(result.installed_path.as_path());
+
+                if !plugin_mcp_servers.is_empty() {
+                    if let Err(err) = self.queue_mcp_server_refresh_for_config(&config).await {
+                        warn!(
+                            plugin = result.plugin_id.as_key(),
+                            "failed to queue MCP refresh after plugin install: {err:?}"
+                        );
+                    }
+                    self.start_plugin_mcp_oauth_logins(&config, plugin_mcp_servers)
+                        .await;
+                }
+
                 let plugin_apps = load_plugin_apps(result.installed_path.as_path());
                 let apps_needing_auth = if plugin_apps.is_empty()
                     || !config.features.apps_enabled(Some(&self.auth_manager)).await
@@ -5802,7 +5825,6 @@ impl CodexMessageProcessor {
                     )
                 };
 
-                self.clear_plugin_related_caches();
                 self.outgoing
                     .send_response(
                         request_id,

codex-rs/app-server/src/codex_message_processor/plugin_mcp_oauth.rs

@@ -0,0 +1,95 @@
+use std::collections::HashMap;
+use std::sync::Arc;
+
+use codex_app_server_protocol::McpServerOauthLoginCompletedNotification;
+use codex_app_server_protocol::ServerNotification;
+use codex_core::config::Config;
+use codex_core::config::types::McpServerConfig;
+use codex_core::mcp::auth::McpOAuthLoginSupport;
+use codex_core::mcp::auth::oauth_login_support;
+use codex_core::mcp::auth::resolve_oauth_scopes;
+use codex_core::mcp::auth::should_retry_without_scopes;
+use codex_rmcp_client::perform_oauth_login;
+use tracing::warn;
+
+use super::CodexMessageProcessor;
+
+impl CodexMessageProcessor {
+    pub(super) async fn start_plugin_mcp_oauth_logins(
+        &self,
+        config: &Config,
+        plugin_mcp_servers: HashMap<String, McpServerConfig>,
+    ) {
+        for (name, server) in plugin_mcp_servers {
+            let oauth_config = match oauth_login_support(&server.transport).await {
+                McpOAuthLoginSupport::Supported(config) => config,
+                McpOAuthLoginSupport::Unsupported => continue,
+                McpOAuthLoginSupport::Unknown(err) => {
+                    warn!(
+                        "MCP server may or may not require login for plugin install {name}: {err}"
+                    );
+                    continue;
+                }
+            };
+
+            let resolved_scopes = resolve_oauth_scopes(
+                /*explicit_scopes*/ None,
+                server.scopes.clone(),
+                oauth_config.discovered_scopes.clone(),
+            );
+
+            let store_mode = config.mcp_oauth_credentials_store_mode;
+            let callback_port = config.mcp_oauth_callback_port;
+            let callback_url = config.mcp_oauth_callback_url.clone();
+            let outgoing = Arc::clone(&self.outgoing);
+            let notification_name = name.clone();
+
+            tokio::spawn(async move {
+                let first_attempt = perform_oauth_login(
+                    &name,
+                    &oauth_config.url,
+                    store_mode,
+                    oauth_config.http_headers.clone(),
+                    oauth_config.env_http_headers.clone(),
+                    &resolved_scopes.scopes,
+                    server.oauth_resource.as_deref(),
+                    callback_port,
+                    callback_url.as_deref(),
+                )
+                .await;
+
+                let final_result = match first_attempt {
+                    Err(err) if should_retry_without_scopes(&resolved_scopes, &err) => {
+                        perform_oauth_login(
+                            &name,
+                            &oauth_config.url,
+                            store_mode,
+                            oauth_config.http_headers,
+                            oauth_config.env_http_headers,
+                            &[],
+                            server.oauth_resource.as_deref(),
+                            callback_port,
+                            callback_url.as_deref(),
+                        )
+                        .await
+                    }
+                    result => result,
+                };
+
+                let (success, error) = match final_result {
+                    Ok(()) => (true, None),
+                    Err(err) => (false, Some(err.to_string())),
+                };
+
+                let notification = ServerNotification::McpServerOauthLoginCompleted(
+                    McpServerOauthLoginCompletedNotification {
+                        name: notification_name,
+                        success,
+                        error,
+                    },
+                );
+                outgoing.send_server_notification(notification).await;
+            });
+        }
+    }
+}

codex-rs/app-server/tests/suite/v2/plugin_install.rs

@@ -529,6 +529,79 @@ async fn plugin_install_filters_disallowed_apps_needing_auth() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test]
+async fn plugin_install_makes_bundled_mcp_servers_available_to_followup_requests() -> Result<()> {
+    let codex_home = TempDir::new()?;
+    std::fs::write(
+        codex_home.path().join("config.toml"),
+        "[features]\nplugins = true\n",
+    )?;
+    let repo_root = TempDir::new()?;
+    write_plugin_marketplace(
+        repo_root.path(),
+        "debug",
+        "sample-plugin",
+        "./sample-plugin",
+        None,
+        None,
+    )?;
+    write_plugin_source(repo_root.path(), "sample-plugin", &[])?;
+    std::fs::write(
+        repo_root.path().join("sample-plugin/.mcp.json"),
+        r#"{
+  "mcpServers": {
+    "sample-mcp": {
+      "command": "echo"
+    }
+  }
+}"#,
+    )?;
+    let marketplace_path =
+        AbsolutePathBuf::try_from(repo_root.path().join(".agents/plugins/marketplace.json"))?;
+
+    let mut mcp = McpProcess::new(codex_home.path()).await?;
+    timeout(DEFAULT_TIMEOUT, mcp.initialize()).await??;
+
+    let request_id = mcp
+        .send_plugin_install_request(PluginInstallParams {
+            marketplace_path,
+            plugin_name: "sample-plugin".to_string(),
+            force_remote_sync: false,
+        })
+        .await?;
+    let response: JSONRPCResponse = timeout(
+        DEFAULT_TIMEOUT,
+        mcp.read_stream_until_response_message(RequestId::Integer(request_id)),
+    )
+    .await??;
+    let response: PluginInstallResponse = to_response(response)?;
+    assert_eq!(response.apps_needing_auth, Vec::<AppSummary>::new());
+    let config = std::fs::read_to_string(codex_home.path().join("config.toml"))?;
+    assert!(!config.contains("[mcp_servers.sample-mcp]"));
+    assert!(!config.contains("command = \"echo\""));
+
+    let request_id = mcp
+        .send_raw_request(
+            "mcpServer/oauth/login",
+            Some(json!({
+                "name": "sample-mcp",
+            })),
+        )
+        .await?;
+    let err = timeout(
+        DEFAULT_TIMEOUT,
+        mcp.read_stream_until_error_message(RequestId::Integer(request_id)),
+    )
+    .await??;
+
+    assert_eq!(err.error.code, -32600);
+    assert_eq!(
+        err.error.message,
+        "OAuth login is only supported for streamable HTTP servers."
+    );
+    Ok(())
+}
+
 #[derive(Clone)]
 struct AppsServerState {
     response: Arc<StdMutex<serde_json::Value>>,

codex-rs/core/src/plugins/manager.rs

@@ -1660,6 +1660,22 @@ pub fn plugin_telemetry_metadata_from_root(
     }
 }
 
+pub fn load_plugin_mcp_servers(plugin_root: &Path) -> HashMap<String, McpServerConfig> {
+    let Some(manifest) = load_plugin_manifest(plugin_root) else {
+        return HashMap::new();
+    };
+
+    let mut mcp_servers = HashMap::new();
+    for mcp_config_path in plugin_mcp_config_paths(plugin_root, &manifest.paths) {
+        let plugin_mcp = load_mcp_servers_from_file(plugin_root, &mcp_config_path);
+        for (name, config) in plugin_mcp.mcp_servers {
+            mcp_servers.entry(name).or_insert(config);
+        }
+    }
+
+    mcp_servers
+}
+
 pub fn installed_plugin_telemetry_metadata(
     codex_home: &Path,
     plugin_id: &PluginId,

codex-rs/core/src/plugins/mod.rs

@@ -36,6 +36,7 @@ pub use manager::PluginsManager;
 pub use manager::RemotePluginSyncResult;
 pub use manager::installed_plugin_telemetry_metadata;
 pub use manager::load_plugin_apps;
+pub use manager::load_plugin_mcp_servers;
 pub(crate) use manager::plugin_namespace_for_skill_path;
 pub use manager::plugin_telemetry_metadata_from_root;
 pub use manifest::PluginManifestInterface;