feat(core): Introduce AgentLoopContext. (#21198)

packages/core/src/config/agent-loop-context.ts

@@ -0,0 +1,27 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import type { GeminiClient } from '../core/client.js';
+import type { MessageBus } from '../confirmation-bus/message-bus.js';
+import type { ToolRegistry } from '../tools/tool-registry.js';
+
+/**
+ * AgentLoopContext represents the execution-scoped view of the world for a single
+ * agent turn or sub-agent loop.
+ */
+export interface AgentLoopContext {
+  /** The unique ID for the current user turn or agent thought loop. */
+  readonly promptId: string;
+
+  /** The registry of tools available to the agent in this context. */
+  readonly toolRegistry: ToolRegistry;
+
+  /** The bus for user confirmations and messages in this context. */
+  readonly messageBus: MessageBus;
+
+  /** The client used to communicate with the LLM in this context. */
+  readonly geminiClient: GeminiClient;
+}