Cleanup: unify HookMessage naming and simplify SessionContext

- Rename HookAppMessage to HookMessage, isHookAppMessage to isHookMessage
- Remove entries array from SessionContext (use isHookMessage type guard instead)
- HookMessage.content now accepts string directly (not just array)
- Fix streamMessage type in AgentState (AppMessage, not Message)
- Rename CustomMessageComponent to HookMessageComponent
- Fix test hook to use pi.sendMessage

packages/coding-agent/src/core/hooks/index.ts

@@ -27,7 +27,6 @@ export type {
 	HookEvent,
 	HookEventContext,
 	HookFactory,
-	HookMessage,
 	HookMessageRenderer,
 	HookMessageRenderOptions,
 	HookUIContext,

packages/coding-agent/src/core/hooks/loader.ts

@@ -9,15 +9,9 @@ import * as path from "node:path";
 import { fileURLToPath } from "node:url";
 import { createJiti } from "jiti";
 import { getAgentDir } from "../../config.js";
+import type { HookMessage } from "../messages.js";
 import { execCommand } from "./runner.js";
-import type {
-	ExecOptions,
-	HookAPI,
-	HookFactory,
-	HookMessage,
-	HookMessageRenderer,
-	RegisteredCommand,
-} from "./types.js";
+import type { ExecOptions, HookAPI, HookFactory, HookMessageRenderer, RegisteredCommand } from "./types.js";
 
 // Create require function to resolve module paths at runtime
 const require = createRequire(import.meta.url);
@@ -56,7 +50,10 @@ type HandlerFn = (...args: unknown[]) => Promise<unknown>;
 /**
  * Send message handler type for pi.sendMessage().
  */
-export type SendMessageHandler = <T = unknown>(message: HookMessage<T>, triggerTurn?: boolean) => void;
+export type SendMessageHandler = <T = unknown>(
+	message: Pick<HookMessage<T>, "customType" | "content" | "display" | "details">,
+	triggerTurn?: boolean,
+) => void;
 
 /**
  * Append entry handler type for pi.appendEntry().

packages/coding-agent/src/core/hooks/types.ts

@@ -11,8 +11,9 @@ import type { Component } from "@mariozechner/pi-tui";
 import type { Theme } from "../../modes/interactive/theme/theme.js";
 import type { CompactionPreparation, CompactionResult } from "../compaction.js";
 import type { ExecOptions, ExecResult } from "../exec.js";
+import type { HookMessage } from "../messages.js";
 import type { ModelRegistry } from "../model-registry.js";
-import type { CompactionEntry, CustomMessageEntry, SessionManager } from "../session-manager.js";
+import type { CompactionEntry, SessionManager } from "../session-manager.js";
 import type { EditToolDetails } from "../tools/edit.js";
 import type {
 	BashToolDetails,
@@ -380,14 +381,6 @@ export interface SessionEventResult {
  */
 export type HookHandler<E, R = void> = (event: E, ctx: HookEventContext) => Promise<R>;
 
-/**
- * Options passed to custom message renderers.
- */
-/**
- * Message type for hooks to send. Creates CustomMessageEntry in the session.
- */
-export type HookMessage<T = unknown> = Pick<CustomMessageEntry<T>, "customType" | "content" | "display" | "details">;
-
 export interface HookMessageRenderOptions {
 	/** Whether the view is expanded */
 	expanded: boolean;
@@ -463,7 +456,10 @@ export interface HookAPI {
 	 * @param triggerTurn - If true and agent is idle, triggers a new LLM turn. Default: false.
 	 *                      If agent is streaming, message is queued and triggerTurn is ignored.
 	 */
-	sendMessage<T = unknown>(message: HookMessage<T>, triggerTurn?: boolean): void;
+	sendMessage<T = unknown>(
+		message: Pick<HookMessage<T>, "customType" | "content" | "display" | "details">,
+		triggerTurn?: boolean,
+	): void;
 
 	/**
 	 * Append a custom entry to the session for hook state persistence.