diff --git a/codex-rs/ext/plugin-installs/src/lib.rs b/codex-rs/ext/plugin-installs/src/lib.rs
index 141881940f..c12ebcfdd2 100644
--- a/codex-rs/ext/plugin-installs/src/lib.rs
+++ b/codex-rs/ext/plugin-installs/src/lib.rs
@@ -1,10 +1,15 @@
 mod domain;
 mod spec;
+mod tool;
 mod validation;
 
 pub const REQUEST_PLUGIN_INSTALLS_TOOL_NAME: &str = "request_plugin_installs";
 pub(crate) const MAX_REQUEST_PLUGIN_INSTALLS_ENTRIES: usize = 16;
 
+use std::future::Future;
+use std::pin::Pin;
+
+use codex_extension_api::FunctionCallError;
 pub use domain::REQUEST_PLUGIN_INSTALL_PERSIST_ALWAYS_VALUE;
 pub use domain::REQUEST_PLUGIN_INSTALL_PERSIST_KEY;
 pub use domain::RequestPluginInstallEntryResult;
@@ -20,4 +25,25 @@ pub use domain::verified_connector_install_completed;
 pub use spec::ToolSuggestPresentation;
 pub use spec::create_request_plugin_installs_tool;
 pub use spec::create_request_plugin_installs_tool_for_tui;
+pub use tool::RequestPluginInstallsMode;
+pub use tool::request_plugin_installs_tool;
 pub use validation::request_plugin_install_picker_completed;
+
+pub type RequestPluginInstallsBackendFuture<'a> = Pin<
+    Box<dyn Future<Output = Result<RequestPluginInstallsResult, FunctionCallError>> + Send + 'a>,
+>;
+
+pub struct RequestPluginInstallsRequest {
+    pub call_id: String,
+    pub turn_id: String,
+    pub args: RequestPluginInstallsArgs,
+    pub resolved_entries: Vec<RequestPluginInstallResolvedPickerEntry>,
+}
+
+/// Host operations needed to complete a plugin install suggestion.
+pub trait RequestPluginInstallsBackend: Send + Sync {
+    fn execute(
+        &self,
+        request: RequestPluginInstallsRequest,
+    ) -> RequestPluginInstallsBackendFuture<'_>;
+}
diff --git a/codex-rs/ext/plugin-installs/src/tool.rs b/codex-rs/ext/plugin-installs/src/tool.rs
new file mode 100644
index 0000000000..6e12aac811
--- /dev/null
+++ b/codex-rs/ext/plugin-installs/src/tool.rs
@@ -0,0 +1,108 @@
+use std::sync::Arc;
+
+use codex_extension_api::FunctionCallError;
+use codex_extension_api::JsonToolOutput;
+use codex_extension_api::ToolCall;
+use codex_extension_api::ToolExecutor;
+use codex_extension_api::ToolName;
+use codex_extension_api::ToolOutput;
+use codex_extension_api::ToolSpec;
+use codex_tools::DiscoverableTool;
+use codex_tools::DiscoverableToolAction;
+
+use crate::REQUEST_PLUGIN_INSTALLS_TOOL_NAME;
+use crate::RequestPluginInstallsArgs;
+use crate::RequestPluginInstallsBackend;
+use crate::RequestPluginInstallsRequest;
+use crate::ToolSuggestPresentation;
+use crate::spec::create_request_plugin_installs_tool;
+use crate::spec::create_request_plugin_installs_tool_for_tui;
+use crate::validation::validate_request_plugin_install_picker_args;
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum RequestPluginInstallsMode {
+    SingleEntry,
+    MultipleEntries,
+}
+
+struct RequestPluginInstallsTool {
+    backend: Arc<dyn RequestPluginInstallsBackend>,
+    discoverable_tools: Vec<DiscoverableTool>,
+    presentation: ToolSuggestPresentation,
+    mode: RequestPluginInstallsMode,
+}
+
+pub fn request_plugin_installs_tool(
+    backend: Arc<dyn RequestPluginInstallsBackend>,
+    discoverable_tools: Vec<DiscoverableTool>,
+    presentation: ToolSuggestPresentation,
+    mode: RequestPluginInstallsMode,
+) -> Arc<dyn ToolExecutor<ToolCall>> {
+    Arc::new(RequestPluginInstallsTool {
+        backend,
+        discoverable_tools,
+        presentation,
+        mode,
+    })
+}
+
+impl ToolExecutor<ToolCall> for RequestPluginInstallsTool {
+    fn tool_name(&self) -> ToolName {
+        ToolName::plain(REQUEST_PLUGIN_INSTALLS_TOOL_NAME)
+    }
+
+    fn spec(&self) -> ToolSpec {
+        match self.mode {
+            RequestPluginInstallsMode::SingleEntry => {
+                create_request_plugin_installs_tool_for_tui(self.presentation)
+            }
+            RequestPluginInstallsMode::MultipleEntries => {
+                create_request_plugin_installs_tool(self.presentation)
+            }
+        }
+    }
+
+    fn handle(&self, call: ToolCall) -> codex_extension_api::ToolExecutorFuture<'_> {
+        Box::pin(self.handle_call(call))
+    }
+}
+
+impl RequestPluginInstallsTool {
+    async fn handle_call(&self, call: ToolCall) -> Result<Box<dyn ToolOutput>, FunctionCallError> {
+        let arguments = call.function_arguments()?;
+        let args: RequestPluginInstallsArgs = serde_json::from_str(arguments).map_err(|err| {
+            FunctionCallError::RespondToModel(format!("failed to parse function arguments: {err}"))
+        })?;
+        if args.action_type != DiscoverableToolAction::Install {
+            return Err(FunctionCallError::RespondToModel(
+                "plugin install requests currently support only action_type=\"install\""
+                    .to_string(),
+            ));
+        }
+        let client_name = match self.mode {
+            RequestPluginInstallsMode::SingleEntry => Some("codex-tui"),
+            RequestPluginInstallsMode::MultipleEntries => None,
+        };
+        let resolved_entries = validate_request_plugin_install_picker_args(
+            &args,
+            &self.discoverable_tools,
+            client_name,
+            self.presentation,
+        )?;
+        let result = self
+            .backend
+            .execute(RequestPluginInstallsRequest {
+                call_id: call.call_id,
+                turn_id: call.turn_id,
+                args,
+                resolved_entries,
+            })
+            .await?;
+        let value = serde_json::to_value(result).map_err(|err| {
+            FunctionCallError::Fatal(format!(
+                "failed to serialize {REQUEST_PLUGIN_INSTALLS_TOOL_NAME} response: {err}"
+            ))
+        })?;
+        Ok(Box::new(JsonToolOutput::with_success(value, Some(true))))
+    }
+}