feat(api): add assigned_agent to Task model (MS22-DB-003, MS22-API-003) (#591)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

apps/api/prisma/migrations/20260301211000_ms22_task_assigned_agent/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "tasks" ADD COLUMN "assigned_agent" TEXT;

apps/api/prisma/schema.prisma

@@ -379,6 +379,7 @@ model Task {
   creatorId   String       @map("creator_id") @db.Uuid
   projectId   String?      @map("project_id") @db.Uuid
   parentId    String?      @map("parent_id") @db.Uuid
+  assignedAgent String?    @map("assigned_agent")
   domainId    String?      @map("domain_id") @db.Uuid
   sortOrder   Int          @default(0) @map("sort_order")
   metadata    Json         @default("{}")

apps/api/src/tasks/dto/create-task.dto.ts

@@ -50,6 +50,12 @@ export class CreateTaskDto {
   @IsUUID("4", { message: "parentId must be a valid UUID" })
   parentId?: string;
 
+  @IsOptional()
+  @IsString({ message: "assignedAgent must be a string" })
+  @MinLength(1, { message: "assignedAgent must not be empty" })
+  @MaxLength(255, { message: "assignedAgent must not exceed 255 characters" })
+  assignedAgent?: string;
+
   @IsOptional()
   @IsInt({ message: "sortOrder must be an integer" })
   @Min(0, { message: "sortOrder must be at least 0" })

apps/api/src/tasks/dto/update-task.dto.ts

@@ -52,6 +52,12 @@ export class UpdateTaskDto {
   @IsUUID("4", { message: "parentId must be a valid UUID" })
   parentId?: string | null;
 
+  @IsOptional()
+  @IsString({ message: "assignedAgent must be a string" })
+  @MinLength(1, { message: "assignedAgent must not be empty" })
+  @MaxLength(255, { message: "assignedAgent must not exceed 255 characters" })
+  assignedAgent?: string | null;
+
   @IsOptional()
   @IsInt({ message: "sortOrder must be an integer" })
   @Min(0, { message: "sortOrder must be at least 0" })

apps/api/src/tasks/tasks.service.spec.ts

@@ -48,6 +48,7 @@ describe("TasksService", () => {
     creatorId: mockUserId,
     projectId: null,
     parentId: null,
+    assignedAgent: null,
     sortOrder: 0,
     metadata: {},
     createdAt: new Date(),
@@ -158,6 +159,28 @@ describe("TasksService", () => {
         })
       );
     });
+
+    it("should include assignedAgent when provided", async () => {
+      const createDto = {
+        title: "Agent-owned Task",
+        assignedAgent: "fleet-worker-1",
+      };
+
+      mockPrismaService.task.create.mockResolvedValue({
+        ...mockTask,
+        assignedAgent: createDto.assignedAgent,
+      });
+
+      await service.create(mockWorkspaceId, mockUserId, createDto);
+
+      expect(prisma.task.create).toHaveBeenCalledWith(
+        expect.objectContaining({
+          data: expect.objectContaining({
+            assignedAgent: createDto.assignedAgent,
+          }),
+        })
+      );
+    });
   });
 
   describe("findAll", () => {
@@ -469,6 +492,26 @@ describe("TasksService", () => {
         service.update(mockTaskId, mockWorkspaceId, mockUserId, { title: "Test" })
       ).rejects.toThrow(NotFoundException);
     });
+
+    it("should update assignedAgent when provided", async () => {
+      const updateDto = { assignedAgent: "fleet-worker-2" };
+
+      mockPrismaService.task.findUnique.mockResolvedValue(mockTask);
+      mockPrismaService.task.update.mockResolvedValue({
+        ...mockTask,
+        assignedAgent: updateDto.assignedAgent,
+      });
+
+      await service.update(mockTaskId, mockWorkspaceId, mockUserId, updateDto);
+
+      expect(prisma.task.update).toHaveBeenCalledWith(
+        expect.objectContaining({
+          data: expect.objectContaining({
+            assignedAgent: updateDto.assignedAgent,
+          }),
+        })
+      );
+    });
   });
 
   describe("remove", () => {

apps/api/src/tasks/tasks.service.ts

@@ -67,6 +67,9 @@ export class TasksService {
       metadata: createTaskDto.metadata
         ? (createTaskDto.metadata as unknown as Prisma.InputJsonValue)
         : {},
+      ...(createTaskDto.assignedAgent !== undefined && {
+        assignedAgent: createTaskDto.assignedAgent,
+      }),
       ...(assigneeConnection && { assignee: assigneeConnection }),
       ...(projectConnection && { project: projectConnection }),
       ...(parentConnection && { parent: parentConnection }),
@@ -291,6 +294,9 @@ export class TasksService {
         if (updateTaskDto.parentId !== undefined && updateTaskDto.parentId !== null) {
           data.parent = { connect: { id: updateTaskDto.parentId } };
         }
+        if (updateTaskDto.assignedAgent !== undefined) {
+          data.assignedAgent = updateTaskDto.assignedAgent;
+        }
 
         // Handle completedAt based on status changes
         if (updateTaskDto.status) {