Refactor how agent are used and add REST API endpoint

README.md

@@ -24,6 +24,42 @@ cd wp-agents && composer install
 wp plugin activate wp-agents
 ```
 
+## REST API
+
+Each agent can be accessed programmatically through the WordPress REST API. 
+
+This allows external systems or front-end applications to send a message to any registered agent and receive the model’s response in JSON format.
+
+**Endpoint**
+
+```bash
+POST /wp-json/wp-agents/v1/chat
+```
+
+**Example**
+
+```bash
+curl --location 'https://example.com/wp-json/wp-agents/v1/chat' \
+--header 'Content-Type: application/json' \
+--data '{
+    "agent": "taxonomy_agent",
+    "message": "Hello"
+}'
+```
+
+**Example response**
+
+```json
+{
+    "agent": "taxonomy_agent",
+    "message": "Hello",
+    "response": {
+        "role": "assistant",
+        "content": "Hello! How can I assist you today?"
+    }
+}
+```
+
 ## Demo
 
 https://github.com/santerref/wp-agents-demo

lib/agents/class-abstract-llm-agent.php

@@ -3,6 +3,8 @@
 namespace Wp_Agents\Agents;
 
 use Wp_Agents\Providers\Provider_Interface;
+use Wp_Agents\Services\Provider_Manager;
+use Wp_Agents\System\Agent_Runner;
 
 abstract class Abstract_Llm_Agent {
 
@@ -12,24 +14,21 @@ abstract class Abstract_Llm_Agent {
 
 	protected bool $json = false;
 
-	protected array $actions = array();
-
 	protected array $filters = array();
 
 	protected array $tools = array();
 
 	abstract public function instructions(): string;
 
-	public function actions(): array {
-		return $this->actions;
-	}
-
 	public function filters(): array {
 		return $this->filters;
 	}
 
-	public function run( mixed $input, Provider_Interface $provider ): mixed {
-		return $provider->complete( $input, $this );
+	public function prompt( mixed $input ): Agent_Runner {
+		return new Agent_Runner(
+			$input,
+			$this
+		);
 	}
 
 	public function get_model(): string {

lib/exceptions/class-agent-not-found-exception.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Wp_Agents\Exceptions;
+
+class Agent_Not_Found_Exception extends \Exception {
+
+}

lib/providers/class-open-ai-provider.php

@@ -3,6 +3,8 @@
 namespace Wp_Agents\Providers;
 
 use Wp_Agents\Agents\Abstract_Llm_Agent;
+use Wp_Agents\System\Message;
+use Wp_Agents\System\Message_Stack;
 use Wp_Agents\Tools\Tool_Registry;
 
 class Open_Ai_Provider implements Provider_Interface {
@@ -13,23 +15,20 @@ public function __construct( string $api_key ) {
 		$this->api_key = $api_key;
 	}
 
-	public function complete( string $prompt, Abstract_Llm_Agent $agent ): string {
+	public function chat( string $input, Abstract_Llm_Agent $agent ): Message_Stack {
 		$client = \OpenAI::client( $this->api_key );
 		$tools  = $agent->tools();
 
-		$messages   = array(
+		$messages = new Message_Stack(
 			array(
-				'role'    => 'system',
-				'content' => $agent->instructions(),
-			),
-			array(
-				'role'    => 'user',
-				'content' => $prompt,
-			),
+				new Message( 'system', $agent->instructions() ),
+				new Message( 'user', $input ),
+			)
 		);
+
 		$parameters = array(
 			'model'           => $agent->get_model(),
-			'messages'        => $messages,
+			'messages'        => $messages->to_raw_array(),
 			'response_format' => array( 'type' => $agent->json() ? 'json_object' : 'text' ),
 		);
 
@@ -40,8 +39,14 @@ public function complete( string $prompt, Abstract_Llm_Agent $agent ): string {
 
 		$response = $client->chat()->create( $parameters );
 
-		$message    = $response->choices[0]->message;
-		$messages[] = $message->toArray();
+		$message = $response->choices[0]->message;
+		$messages->add(
+			new Message(
+				$message->role,
+				$message->content,
+				$message->toArray()
+			)
+		);
 
 		// phpcs:ignore WordPress.NamingConventions.ValidVariableName
 		if ( ! empty( $message->toolCalls ) ) {
@@ -55,24 +60,35 @@ public function complete( string $prompt, Abstract_Llm_Agent $agent ): string {
 				}
 				$result = $tool_registry->execute( $function->name, $args );
 
-				$messages[] = array(
-					'role'         => 'tool',
-					'tool_call_id' => $call->id,
-					'content'      => wp_json_encode( $result ),
+				$messages->add(
+					new Message(
+						'tool',
+						wp_json_encode( $result ),
+						array(
+							'tool_call_id' => $call->id,
+						)
+					)
 				);
 			}
 
 			$follow = $client->chat()->create(
 				array(
 					'model'           => $agent->get_model(),
-					'messages'        => $messages,
+					'messages'        => $messages->to_raw_array(),
 					'response_format' => array( 'type' => $agent->json() ? 'json_object' : 'text' ),
 				)
 			);
 
-			return $follow->choices[0]->message->content ?? '';
+			$message = $follow->choices[0]->message;
+			$messages->add(
+				new Message(
+					$message->role,
+					$message->content,
+					$message->toArray(),
+				)
+			);
 		}
 
-		return $response->choices[0]->message->content ?? '';
+		return $messages;
 	}
 }

lib/providers/class-provider-interface.php

@@ -3,8 +3,9 @@
 namespace Wp_Agents\Providers;
 
 use Wp_Agents\Agents\Abstract_Llm_Agent;
+use Wp_Agents\System\Message_Stack;
 
 interface Provider_Interface {
 
-	public function complete( string $prompt, Abstract_Llm_Agent $agent ): string;
+	public function chat( string $input, Abstract_Llm_Agent $agent ): Message_Stack;
 }

lib/services/class-agent-manager.php

@@ -3,42 +3,22 @@
 namespace Wp_Agents\Services;
 
 use Wp_Agents\Agents\Abstract_Llm_Agent;
-use Wp_Agents\Exceptions\Skip_Agent_Exception;
+use Wp_Agents\Exceptions\Agent_Not_Found_Exception;
 
 class Agent_Manager {
 
 	protected static array $agents = array();
 
-	public static function register( string $name, Abstract_Llm_Agent $agent ): void {
-		self::$agents[ $name ] = $agent;
-
-		foreach ( $agent->actions() as $action ) {
-			$input = Input_Manager::make( $action );
-
-			add_action(
-				$action,
-				function ( ...$args ) use ( $agent, $input, $name, $action ) {
-					Recursion_Guard::run(
-						"{$name}:{$action}",
-						function () use ( $input, $args, $agent ) {
-							try {
-								$built_input = $input->build( ...$args );
-								if ( ! empty( $built_input ) ) {
-									$provider = Provider_Manager::get( $agent->get_provider() );
-									$answer   = $agent->run( $built_input, $provider );
-									$agent->handle_response( $answer, $args );
-								}
-							} catch ( Skip_Agent_Exception $e ) {
-								wp_agents_logger()->error( $e->getMessage() );
-							}
-						}
-					);
-				},
-				$input->get_priority(),
-				$input->get_accepted_args()
-			);
+	public static function register( string $name, string $agent_class ): void {
+		self::$agents[ $name ] = new $agent_class();
+	}
 
+	public static function get( string $name ): Abstract_Llm_Agent {
+		if ( ! isset( self::$agents[ $name ] ) ) {
+			throw new Agent_Not_Found_Exception();
 		}
+
+		return self::$agents[ $name ];
 	}
 
 	public static function boot(): void {

lib/system/class-agent-runner.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Wp_Agents\System;
+
+use Wp_Agents\Agents\Abstract_Llm_Agent;
+use Wp_Agents\Providers\Provider_Interface;
+use Wp_Agents\Services\Provider_Manager;
+
+class Agent_Runner {
+
+	protected string $input;
+
+	protected Provider_Interface $provider;
+
+	protected Abstract_Llm_Agent $agent;
+
+	public function __construct( string $input, Abstract_Llm_Agent $agent ) {
+		$this->input    = $input;
+		$this->agent    = $agent;
+		$this->provider = Provider_Manager::get( $agent->get_provider() );
+	}
+
+	public function chat(): Message {
+		$message_stack = $this->provider->chat( $this->input, $this->agent );
+
+		return $message_stack->last();
+	}
+}