fix: resolve agent_report even if parent history write fails

Change-Id: I4febc00a10f55517b9ec272b9fa834d606a98ef9
Signed-off-by: Thomas Kosiewski <tk@coder.com>

Author: ThomasK33

src/node/services/taskService.test.ts

@@ -258,6 +258,96 @@ describe("TaskService", () => {
     });
   });
 
+  describe("handleAgentReport", () => {
+    it("should resolve awaiters even if parent history append fails", async () => {
+      const parentWorkspaceId = "parent";
+      const childWorkspaceId = "child";
+
+      const workspace = {
+        id: childWorkspaceId,
+        path: "/tmp/agent",
+        name: "agent",
+        projectName: "proj",
+        projectPath: "/proj",
+        createdAt: "2025-01-01T00:00:00.000Z",
+        parentWorkspaceId,
+        agentType: "research",
+        taskStatus: "running",
+        taskModel: "openai:gpt-5-codex",
+      };
+
+      const projects = new Map([
+        [
+          "/proj",
+          {
+            workspaces: [workspace],
+          },
+        ],
+      ]);
+
+      let idCounter = 0;
+      const config = {
+        generateStableId: () => `id-${idCounter++}`,
+        getTaskSettings: () => ({
+          maxParallelAgentTasks: 3,
+          maxTaskNestingDepth: 3,
+        }),
+        listWorkspaceConfigs: () => [],
+        getWorkspaceConfig: (id: string) => {
+          if (id !== childWorkspaceId) {
+            return null;
+          }
+
+          return { projectPath: "/proj", workspace };
+        },
+        editConfig: (edit: (cfg: unknown) => unknown) => {
+          edit({ projects });
+        },
+      };
+
+      const historyService = {
+        getHistory: (_workspaceId: string) => Ok([]),
+        appendToHistory: (workspaceId: string, _message: MuxMessage) => {
+          if (workspaceId === parentWorkspaceId) {
+            return Err("disk full");
+          }
+
+          return Ok(undefined);
+        },
+      };
+
+      const partialService = {
+        readPartial: () => null,
+        writePartial: () => Ok(undefined),
+      };
+
+      const workspaceService = {
+        emitChatEvent: (_workspaceId: string, _event: unknown) => undefined,
+        emitWorkspaceMetadata: (_workspaceId: string) => undefined,
+        remove: (_workspaceId: string, _force?: boolean) => Ok(undefined),
+      };
+
+      const aiService = {
+        on: () => undefined,
+      };
+
+      const service = new TaskService(
+        config as never,
+        historyService as never,
+        partialService as never,
+        workspaceService as never,
+        aiService as never
+      );
+
+      const reportPromise = service.awaitAgentReport(childWorkspaceId);
+
+      await service.handleAgentReport(childWorkspaceId, { reportMarkdown: "hello" });
+
+      expect(await reportPromise).toEqual({ reportMarkdown: "hello" });
+      expect(workspace.taskStatus).toBe("reported");
+    });
+  });
+
   describe("onStreamEnd", () => {
     it("should finalize tasks when report enforcement resume fails", async () => {
       const parentWorkspaceId = "parent";

src/node/services/taskService.ts

@@ -401,10 +401,13 @@ export class TaskService {
       return;
     }
 
-    // Mark reported.
-    await this.updateTaskWorkspace(workspaceId, {
-      taskStatus: "reported",
-    });
+    // Resolve any in-flight tool call awaiters first so foreground `task` calls don't hang even if
+    // persisting the report to parent history fails.
+    const deferred = this.pendingReportByWorkspaceId.get(workspaceId);
+    if (deferred) {
+      deferred.resolve(report);
+      this.pendingReportByWorkspaceId.delete(workspaceId);
+    }
 
     const preset = workspaceConfig.workspace.agentType
       ? getAgentPreset(workspaceConfig.workspace.agentType)
@@ -425,20 +428,22 @@ export class TaskService {
       reportMessage
     );
     if (!appendResult.success) {
-      throw new Error(appendResult.error);
+      log.error("Failed to append subagent report to parent history", {
+        workspaceId,
+        parentWorkspaceId,
+        error: appendResult.error,
+      });
+    } else {
+      this.workspaceService.emitChatEvent(parentWorkspaceId, {
+        ...reportMessage,
+        type: "message",
+      } satisfies WorkspaceChatMessage);
     }
 
-    this.workspaceService.emitChatEvent(parentWorkspaceId, {
-      ...reportMessage,
-      type: "message",
-    } satisfies WorkspaceChatMessage);
-
-    // Resolve any in-flight tool call awaiters.
-    const deferred = this.pendingReportByWorkspaceId.get(workspaceId);
-    if (deferred) {
-      deferred.resolve(report);
-      this.pendingReportByWorkspaceId.delete(workspaceId);
-    }
+    // Mark reported after best-effort delivery to the parent.
+    await this.updateTaskWorkspace(workspaceId, {
+      taskStatus: "reported",
+    });
 
     // Durable tool output + auto-resume for interrupted parent streams.
     const parentToolCallId = workspaceConfig.workspace.taskParentToolCallId;