Q141: reply to a specific message in its thread, and see what each reply answers

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/shared/chat-domain.ts

@@ -89,3 +89,11 @@ export interface ChatReadStateRecord {
   lastReadMessageId: string | null;
   lastReadAt: string;
 }
+
+/** One thread in full, loaded on demand because the snapshot holds only recent chat. */
+export interface ThreadHistory {
+  messages: ChatMessageRecord[];
+  attachments: ChatAttachmentRecord[];
+  mentions: ChatMentionRecord[];
+  slashInvocations: ChatSlashInvocationRecord[];
+}

src/shared/desktop-api.ts

@@ -1,3 +1,4 @@
+import type { ThreadHistory } from "./chat-domain";
 import type { RunRequestRecord } from "./provider-runtime-domain";
 import type { ApprovalDrift } from "./approval-pin";
 import type { DesktopResult } from "./result";
@@ -195,6 +196,8 @@ export interface DesktopApi {
   approvalDrifts(input: { orgId: string }): Promise<DesktopResult<Record<string, ApprovalDrift>>>;
   /** Every model call a task run made, in order: turns, goal audits and model checks. */
   runRequests(input: { orgId: string; runId: string }): Promise<DesktopResult<RunRequestRecord[]>>;
+  /** One thread in full, beyond the snapshot's recent window. */
+  chatThreadHistory(input: { orgId: string; threadId: string }): Promise<DesktopResult<ThreadHistory>>;
   revokeConnector(input: RevokeConnectorInput): Promise<DesktopResult<AppSnapshot>>;
   search(input: SearchInput): Promise<DesktopResult<SearchResultRecord[]>>;
   subscribe(callback: (event: RendererEvent) => void): () => void;

src/shared/ipc.ts

@@ -81,6 +81,7 @@ export const IPC_CHANNELS = {
   grantConnector: "agentcompany:grant-connector",
   approvalDrifts: "agentcompany:approval-drifts",
   runRequests: "agentcompany:run-requests",
+  chatThreadHistory: "agentcompany:chat-thread-history",
   revokeConnector: "agentcompany:revoke-connector",
   search: "agentcompany:search",
   rendererEvent: "agentcompany:renderer-event",