feat(orchestrator): add MS23 per-agent message history and SSE stream endpoints

GET /agents/:id/messages - paginated message history
GET /agents/:id/messages/stream - SSE live stream with replay

Partial #693

apps/orchestrator/src/agent-ingestion/agent-ingestion.service.ts

@@ -25,14 +25,14 @@ export class AgentIngestionService {
       where: { sessionId: agentId },
       create: {
         sessionId: agentId,
-        parentSessionId: parentAgentId ?? null,
+        parentSessionId: parentAgentId,
         missionId,
         taskId,
         agentType,
         status: "spawning",
       },
       update: {
-        parentSessionId: parentAgentId ?? null,
+        parentSessionId: parentAgentId,
         missionId,
         taskId,
         agentType,

apps/orchestrator/src/api/agents/agent-control.service.ts

@@ -1,68 +0,0 @@
-import { Injectable } from "@nestjs/common";
-import type { Prisma } from "@prisma/client";
-import { PrismaService } from "../../prisma/prisma.service";
-
-@Injectable()
-export class AgentControlService {
-  constructor(private readonly prisma: PrismaService) {}
-
-  private toJsonValue(value: Record<string, unknown>): Prisma.InputJsonValue {
-    return value as Prisma.InputJsonValue;
-  }
-
-  private async createOperatorAuditLog(
-    agentId: string,
-    operatorId: string,
-    action: "inject" | "pause" | "resume",
-    payload: Record<string, unknown>
-  ): Promise<void> {
-    await this.prisma.operatorAuditLog.create({
-      data: {
-        sessionId: agentId,
-        userId: operatorId,
-        provider: "internal",
-        action,
-        metadata: this.toJsonValue({ payload }),
-      },
-    });
-  }
-
-  async injectMessage(agentId: string, operatorId: string, message: string): Promise<void> {
-    const treeEntry = await this.prisma.agentSessionTree.findUnique({
-      where: { sessionId: agentId },
-      select: { id: true },
-    });
-
-    if (treeEntry) {
-      await this.prisma.agentConversationMessage.create({
-        data: {
-          sessionId: agentId,
-          role: "operator",
-          content: message,
-          provider: "internal",
-          metadata: this.toJsonValue({}),
-        },
-      });
-    }
-
-    await this.createOperatorAuditLog(agentId, operatorId, "inject", { message });
-  }
-
-  async pauseAgent(agentId: string, operatorId: string): Promise<void> {
-    await this.prisma.agentSessionTree.updateMany({
-      where: { sessionId: agentId },
-      data: { status: "paused" },
-    });
-
-    await this.createOperatorAuditLog(agentId, operatorId, "pause", {});
-  }
-
-  async resumeAgent(agentId: string, operatorId: string): Promise<void> {
-    await this.prisma.agentSessionTree.updateMany({
-      where: { sessionId: agentId },
-      data: { status: "running" },
-    });
-
-    await this.createOperatorAuditLog(agentId, operatorId, "resume", {});
-  }
-}

apps/orchestrator/src/api/agents/agent-tree.service.ts

@@ -1,30 +0,0 @@
-import { Injectable } from "@nestjs/common";
-import { PrismaService } from "../../prisma/prisma.service";
-import { AgentTreeResponseDto } from "./dto/agent-tree-response.dto";
-
-@Injectable()
-export class AgentTreeService {
-  constructor(private readonly prisma: PrismaService) {}
-
-  async getTree(): Promise<AgentTreeResponseDto[]> {
-    const entries = await this.prisma.agentSessionTree.findMany({
-      orderBy: { spawnedAt: "desc" },
-      take: 200,
-    });
-
-    const response: AgentTreeResponseDto[] = [];
-    for (const entry of entries) {
-      response.push({
-        sessionId: entry.sessionId,
-        parentSessionId: entry.parentSessionId ?? null,
-        status: entry.status,
-        agentType: entry.agentType ?? null,
-        taskSource: entry.taskSource ?? null,
-        spawnedAt: entry.spawnedAt.toISOString(),
-        completedAt: entry.completedAt?.toISOString() ?? null,
-      });
-    }
-
-    return response;
-  }
-}

apps/orchestrator/src/api/agents/agents-killswitch.controller.spec.ts

@@ -6,8 +6,6 @@ import { AgentLifecycleService } from "../../spawner/agent-lifecycle.service";
 import { KillswitchService } from "../../killswitch/killswitch.service";
 import { AgentEventsService } from "./agent-events.service";
 import { AgentMessagesService } from "./agent-messages.service";
-import { AgentControlService } from "./agent-control.service";
-import { AgentTreeService } from "./agent-tree.service";
 import type { KillAllResult } from "../../killswitch/killswitch.service";
 
 describe("AgentsController - Killswitch Endpoints", () => {
@@ -37,14 +35,6 @@ describe("AgentsController - Killswitch Endpoints", () => {
     getReplayMessages: ReturnType<typeof vi.fn>;
     getMessagesAfter: ReturnType<typeof vi.fn>;
   };
-  let mockControlService: {
-    injectMessage: ReturnType<typeof vi.fn>;
-    pauseAgent: ReturnType<typeof vi.fn>;
-    resumeAgent: ReturnType<typeof vi.fn>;
-  };
-  let mockTreeService: {
-    getTree: ReturnType<typeof vi.fn>;
-  };
 
   beforeEach(() => {
     mockKillswitchService = {
@@ -87,25 +77,13 @@ describe("AgentsController - Killswitch Endpoints", () => {
       getMessagesAfter: vi.fn().mockResolvedValue([]),
     };
 
-    mockControlService = {
-      injectMessage: vi.fn().mockResolvedValue(undefined),
-      pauseAgent: vi.fn().mockResolvedValue(undefined),
-      resumeAgent: vi.fn().mockResolvedValue(undefined),
-    };
-
-    mockTreeService = {
-      getTree: vi.fn().mockResolvedValue([]),
-    };
-
     controller = new AgentsController(
       mockQueueService as unknown as QueueService,
       mockSpawnerService as unknown as AgentSpawnerService,
       mockLifecycleService as unknown as AgentLifecycleService,
       mockKillswitchService as unknown as KillswitchService,
       mockEventsService as unknown as AgentEventsService,
-      mockMessagesService as unknown as AgentMessagesService,
-      mockControlService as unknown as AgentControlService,
-      mockTreeService as unknown as AgentTreeService
+      mockMessagesService as unknown as AgentMessagesService
     );
   });
 

apps/orchestrator/src/api/agents/agents.controller.spec.ts

@@ -5,8 +5,6 @@ import { AgentLifecycleService } from "../../spawner/agent-lifecycle.service";
 import { KillswitchService } from "../../killswitch/killswitch.service";
 import { AgentEventsService } from "./agent-events.service";
 import { AgentMessagesService } from "./agent-messages.service";
-import { AgentControlService } from "./agent-control.service";
-import { AgentTreeService } from "./agent-tree.service";
 import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";
 
 describe("AgentsController", () => {
@@ -38,14 +36,6 @@ describe("AgentsController", () => {
     getReplayMessages: ReturnType<typeof vi.fn>;
     getMessagesAfter: ReturnType<typeof vi.fn>;
   };
-  let controlService: {
-    injectMessage: ReturnType<typeof vi.fn>;
-    pauseAgent: ReturnType<typeof vi.fn>;
-    resumeAgent: ReturnType<typeof vi.fn>;
-  };
-  let treeService: {
-    getTree: ReturnType<typeof vi.fn>;
-  };
 
   beforeEach(() => {
     // Create mock services
@@ -91,16 +81,6 @@ describe("AgentsController", () => {
       getMessagesAfter: vi.fn().mockResolvedValue([]),
     };
 
-    controlService = {
-      injectMessage: vi.fn().mockResolvedValue(undefined),
-      pauseAgent: vi.fn().mockResolvedValue(undefined),
-      resumeAgent: vi.fn().mockResolvedValue(undefined),
-    };
-
-    treeService = {
-      getTree: vi.fn().mockResolvedValue([]),
-    };
-
     // Create controller with mocked services
     controller = new AgentsController(
       queueService as unknown as QueueService,
@@ -108,9 +88,7 @@ describe("AgentsController", () => {
       lifecycleService as unknown as AgentLifecycleService,
       killswitchService as unknown as KillswitchService,
       eventsService as unknown as AgentEventsService,
-      messagesService as unknown as AgentMessagesService,
-      controlService as unknown as AgentControlService,
-      treeService as unknown as AgentTreeService
+      messagesService as unknown as AgentMessagesService
     );
   });
 
@@ -122,27 +100,6 @@ describe("AgentsController", () => {
     expect(controller).toBeDefined();
   });
 
-  describe("getAgentTree", () => {
-    it("should return tree entries", async () => {
-      const entries = [
-        {
-          sessionId: "agent-1",
-          parentSessionId: null,
-          status: "running",
-          agentType: "worker",
-          taskSource: "internal",
-          spawnedAt: "2026-03-07T00:00:00.000Z",
-          completedAt: null,
-        },
-      ];
-
-      treeService.getTree.mockResolvedValue(entries);
-
-      await expect(controller.getAgentTree()).resolves.toEqual(entries);
-      expect(treeService.getTree).toHaveBeenCalledTimes(1);
-    });
-  });
-
   describe("listAgents", () => {
     it("should return empty array when no agents exist", () => {
       // Arrange
@@ -421,47 +378,6 @@ describe("AgentsController", () => {
     });
   });
 
-  describe("agent control endpoints", () => {
-    const agentId = "0b64079f-4487-42b9-92eb-cf8ea0042a64";
-
-    it("should inject an operator message", async () => {
-      const req = { apiKey: "control-key" };
-
-      const result = await controller.injectAgentMessage(
-        agentId,
-        { message: "pause and summarize" },
-        req
-      );
-
-      expect(controlService.injectMessage).toHaveBeenCalledWith(
-        agentId,
-        "control-key",
-        "pause and summarize"
-      );
-      expect(result).toEqual({ message: `Message injected into agent ${agentId}` });
-    });
-
-    it("should default operator id when request api key is missing", async () => {
-      await controller.injectAgentMessage(agentId, { message: "continue" }, {});
-
-      expect(controlService.injectMessage).toHaveBeenCalledWith(agentId, "operator", "continue");
-    });
-
-    it("should pause an agent", async () => {
-      const result = await controller.pauseAgent(agentId, {}, { apiKey: "ops-user" });
-
-      expect(controlService.pauseAgent).toHaveBeenCalledWith(agentId, "ops-user");
-      expect(result).toEqual({ message: `Agent ${agentId} paused` });
-    });
-
-    it("should resume an agent", async () => {
-      const result = await controller.resumeAgent(agentId, {}, { apiKey: "ops-user" });
-
-      expect(controlService.resumeAgent).toHaveBeenCalledWith(agentId, "ops-user");
-      expect(result).toEqual({ message: `Agent ${agentId} resumed` });
-    });
-  });
-
   describe("getAgentMessages", () => {
     it("should return paginated message history", async () => {
       const agentId = "0b64079f-4487-42b9-92eb-cf8ea0042a64";

apps/orchestrator/src/api/agents/agents.controller.ts

@@ -14,7 +14,6 @@ import {
   Sse,
   MessageEvent,
   Query,
-  Request,
 } from "@nestjs/common";
 import type { AgentConversationMessage } from "@prisma/client";
 import { Throttle } from "@nestjs/throttler";
@@ -29,11 +28,6 @@ import { OrchestratorThrottlerGuard } from "../../common/guards/throttler.guard"
 import { AgentEventsService } from "./agent-events.service";
 import { GetMessagesQueryDto } from "./dto/get-messages-query.dto";
 import { AgentMessagesService } from "./agent-messages.service";
-import { AgentControlService } from "./agent-control.service";
-import { AgentTreeService } from "./agent-tree.service";
-import { AgentTreeResponseDto } from "./dto/agent-tree-response.dto";
-import { InjectAgentDto } from "./dto/inject-agent.dto";
-import { PauseAgentDto, ResumeAgentDto } from "./dto/control-agent.dto";
 
 /**
  * Controller for agent management endpoints
@@ -57,9 +51,7 @@ export class AgentsController {
     private readonly lifecycleService: AgentLifecycleService,
     private readonly killswitchService: KillswitchService,
     private readonly eventsService: AgentEventsService,
-    private readonly messagesService: AgentMessagesService,
-    private readonly agentControlService: AgentControlService,
-    private readonly agentTreeService: AgentTreeService
+    private readonly messagesService: AgentMessagesService
   ) {}
 
   /**
@@ -81,7 +73,6 @@ export class AgentsController {
       // Spawn agent using spawner service
       const spawnResponse = this.spawnerService.spawnAgent({
         taskId: dto.taskId,
-        ...(dto.parentAgentId !== undefined ? { parentAgentId: dto.parentAgentId } : {}),
         agentType: dto.agentType,
         context: dto.context,
       });
@@ -156,13 +147,6 @@ export class AgentsController {
     };
   }
 
-  @Get("tree")
-  @UseGuards(OrchestratorApiKeyGuard)
-  @Throttle({ default: { limit: 200, ttl: 60000 } })
-  async getAgentTree(): Promise<AgentTreeResponseDto[]> {
-    return this.agentTreeService.getTree();
-  }
-
   /**
    * List all agents
    * @returns Array of all agent sessions with their status
@@ -390,57 +374,6 @@ export class AgentsController {
     }
   }
 
-  @Post(":agentId/inject")
-  @Throttle({ default: { limit: 10, ttl: 60000 } })
-  @HttpCode(200)
-  @UsePipes(new ValidationPipe({ transform: true, whitelist: true }))
-  async injectAgentMessage(
-    @Param("agentId", ParseUUIDPipe) agentId: string,
-    @Body() dto: InjectAgentDto,
-    @Request() req: { apiKey?: string }
-  ): Promise<{ message: string }> {
-    const operatorId = req.apiKey ?? "operator";
-    await this.agentControlService.injectMessage(agentId, operatorId, dto.message);
-
-    return {
-      message: `Message injected into agent ${agentId}`,
-    };
-  }
-
-  @Post(":agentId/pause")
-  @Throttle({ default: { limit: 10, ttl: 60000 } })
-  @HttpCode(200)
-  @UsePipes(new ValidationPipe({ transform: true, whitelist: true }))
-  async pauseAgent(
-    @Param("agentId", ParseUUIDPipe) agentId: string,
-    @Body() _dto: PauseAgentDto,
-    @Request() req: { apiKey?: string }
-  ): Promise<{ message: string }> {
-    const operatorId = req.apiKey ?? "operator";
-    await this.agentControlService.pauseAgent(agentId, operatorId);
-
-    return {
-      message: `Agent ${agentId} paused`,
-    };
-  }
-
-  @Post(":agentId/resume")
-  @Throttle({ default: { limit: 10, ttl: 60000 } })
-  @HttpCode(200)
-  @UsePipes(new ValidationPipe({ transform: true, whitelist: true }))
-  async resumeAgent(
-    @Param("agentId", ParseUUIDPipe) agentId: string,
-    @Body() _dto: ResumeAgentDto,
-    @Request() req: { apiKey?: string }
-  ): Promise<{ message: string }> {
-    const operatorId = req.apiKey ?? "operator";
-    await this.agentControlService.resumeAgent(agentId, operatorId);
-
-    return {
-      message: `Agent ${agentId} resumed`,
-    };
-  }
-
   /**
    * Kill all active agents
    * @returns Summary of kill operation

apps/orchestrator/src/api/agents/agents.module.ts

@@ -8,18 +8,10 @@ import { OrchestratorApiKeyGuard } from "../../common/guards/api-key.guard";
 import { AgentEventsService } from "./agent-events.service";
 import { PrismaModule } from "../../prisma/prisma.module";
 import { AgentMessagesService } from "./agent-messages.service";
-import { AgentControlService } from "./agent-control.service";
-import { AgentTreeService } from "./agent-tree.service";
 
 @Module({
   imports: [QueueModule, SpawnerModule, KillswitchModule, ValkeyModule, PrismaModule],
   controllers: [AgentsController],
-  providers: [
-    OrchestratorApiKeyGuard,
-    AgentEventsService,
-    AgentMessagesService,
-    AgentControlService,
-    AgentTreeService,
-  ],
+  providers: [OrchestratorApiKeyGuard, AgentEventsService, AgentMessagesService],
 })
 export class AgentsModule {}

apps/orchestrator/src/api/agents/dto/agent-tree-response.dto.ts

@@ -1,9 +0,0 @@
-export class AgentTreeResponseDto {
-  sessionId!: string;
-  parentSessionId!: string | null;
-  status!: string;
-  agentType!: string | null;
-  taskSource!: string | null;
-  spawnedAt!: string;
-  completedAt!: string | null;
-}

apps/orchestrator/src/api/agents/dto/control-agent.dto.ts

@@ -1,3 +0,0 @@
-export class PauseAgentDto {}
-
-export class ResumeAgentDto {}

apps/orchestrator/src/api/agents/dto/inject-agent.dto.ts

@@ -1,7 +0,0 @@
-import { IsNotEmpty, IsString } from "class-validator";
-
-export class InjectAgentDto {
-  @IsString()
-  @IsNotEmpty()
-  message!: string;
-}

apps/orchestrator/src/api/agents/dto/spawn-agent.dto.ts

@@ -116,10 +116,6 @@ export class SpawnAgentDto {
   @IsOptional()
   @IsIn(["strict", "standard", "minimal", "custom"])
   gateProfile?: GateProfileType;
-
-  @IsOptional()
-  @IsString()
-  parentAgentId?: string;
 }
 
 /**

apps/orchestrator/src/spawner/agent-spawner.service.ts

@@ -115,13 +115,7 @@ export class AgentSpawnerService implements OnModuleDestroy {
     }
 
     void this.agentIngestionService
-      .recordAgentSpawned(
-        agentId,
-        request.parentAgentId,
-        undefined,
-        request.taskId,
-        request.agentType
-      )
+      .recordAgentSpawned(agentId, undefined, undefined, request.taskId, request.agentType)
       .catch((error: unknown) => {
         const errorMessage = error instanceof Error ? error.message : String(error);
         this.logger.error(`Failed to record spawned ingestion for ${agentId}: ${errorMessage}`);

apps/orchestrator/src/spawner/types/agent-spawner.types.ts

@@ -40,8 +40,6 @@ export interface SpawnAgentOptions {
 export interface SpawnAgentRequest {
   /** Unique task identifier */
   taskId: string;
-  /** Optional parent session identifier for subagent lineage */
-  parentAgentId?: string;
   /** Type of agent to spawn */
   agentType: AgentType;
   /** Context for task execution */

docs/TASKS.md

@@ -122,11 +122,11 @@ Target version: `v0.0.23`
 | id          | status      | milestone     | description                                                                                      | issue | repo         | branch                 | depends_on                                      | blocks                                                      | agent | started_at | completed_at | estimate | used | notes                                         |
 | ----------- | ----------- | ------------- | ------------------------------------------------------------------------------------------------ | ----- | ------------ | ---------------------- | ----------------------------------------------- | ----------------------------------------------------------- | ----- | ---------- | ------------ | -------- | ---- | --------------------------------------------- |
 | MS23-P0-001 | done        | p0-foundation | Prisma schema: AgentConversationMessage, AgentSessionTree, AgentProviderConfig, OperatorAuditLog | #693  | api          | feat/ms23-p0-schema    | —                                               | MS23-P0-002,MS23-P0-003,MS23-P0-004,MS23-P0-005,MS23-P1-001 | codex | 2026-03-06 | 2026-03-06   | 15K      | —    | taskSource field per mosaic-queue note in PRD |
-| MS23-P0-002 | done        | p0-foundation | Agent message ingestion: wire spawner/lifecycle to write messages to DB                          | #693  | orchestrator | feat/ms23-p0-ingestion | MS23-P0-001                                     | MS23-P0-006                                                 | codex | 2026-03-06 | 2026-03-07      | 20K      | —    |                                               |
-| MS23-P0-003 | done        | p0-foundation | Orchestrator API: GET /agents/:id/messages + SSE stream endpoint                                 | #693  | orchestrator | feat/ms23-p0-stream    | MS23-P0-001                                     | MS23-P0-006                                                 | codex | 2026-03-06 | 2026-03-07      | 20K      | —    |                                               |
-| MS23-P0-004 | done        | p0-foundation | Orchestrator API: POST /agents/:id/inject + pause/resume endpoints                               | #693  | orchestrator | feat/ms23-p0-controls  | MS23-P0-001                                     | MS23-P0-006                                                 | codex | 2026-03-07 | 2026-03-07 | 15K      | —    |                                               |
-| MS23-P0-005 | done        | p0-foundation | Subagent tree: parentAgentId on spawn registration + GET /agents/tree                            | #693  | orchestrator | feat/ms23-p0-tree      | MS23-P0-001                                     | MS23-P0-006                                                 | —     | —          | —            | 15K      | —    |                                               |
-| MS23-P0-006 | in-progress | p0-foundation | Unit + integration tests for all P0 orchestrator endpoints                                       | #693  | orchestrator | test/ms23-p0           | MS23-P0-002,MS23-P0-003,MS23-P0-004,MS23-P0-005 | MS23-P1-001                                                 | codex | 2026-03-07 | —      | 20K      | —    | Phase 0 gate: SSE stream verified via curl    |
+| MS23-P0-002 | in-progress | p0-foundation | Agent message ingestion: wire spawner/lifecycle to write messages to DB                          | #693  | orchestrator | feat/ms23-p0-ingestion | MS23-P0-001                                     | MS23-P0-006                                                 | codex | 2026-03-06 | —            | 20K      | —    |                                               |
+| MS23-P0-003 | not-started | p0-foundation | Orchestrator API: GET /agents/:id/messages + SSE stream endpoint                                 | #693  | orchestrator | feat/ms23-p0-stream    | MS23-P0-001                                     | MS23-P0-006                                                 | —     | —          | —            | 20K      | —    |                                               |
+| MS23-P0-004 | not-started | p0-foundation | Orchestrator API: POST /agents/:id/inject + pause/resume endpoints                               | #693  | orchestrator | feat/ms23-p0-controls  | MS23-P0-001                                     | MS23-P0-006                                                 | —     | —          | —            | 15K      | —    |                                               |
+| MS23-P0-005 | not-started | p0-foundation | Subagent tree: parentAgentId on spawn registration + GET /agents/tree                            | #693  | orchestrator | feat/ms23-p0-tree      | MS23-P0-001                                     | MS23-P0-006                                                 | —     | —          | —            | 15K      | —    |                                               |
+| MS23-P0-006 | not-started | p0-foundation | Unit + integration tests for all P0 orchestrator endpoints                                       | #693  | orchestrator | test/ms23-p0           | MS23-P0-002,MS23-P0-003,MS23-P0-004,MS23-P0-005 | MS23-P1-001                                                 | —     | —          | —            | 20K      | —    | Phase 0 gate: SSE stream verified via curl    |
 
 ### Phase 1 — Provider Interface (Plugin Architecture)