diff --git a/backend/src/middleware/auth.middleware.ts b/backend/src/middleware/auth.middleware.ts
index 1f76d79..2c9c071 100644
--- a/backend/src/middleware/auth.middleware.ts
+++ b/backend/src/middleware/auth.middleware.ts
@@ -16,7 +16,7 @@ export async function authenticate(req: Request, _res: Response, next: NextFunct
     }
     const user = await userRepo.findById(claims.sub);
     if (!user || !user.isActive) throw unauthorized();
-    req.actor = { id: user._id.toString(), role: user.role };
+    req.actor = { id: user._id.toString(), role: user.role, kind: 'human' };
     req.sessionId = claims.sid;
     next();
   } catch (err) {
diff --git a/backend/src/models/agent-config-audit.model.ts b/backend/src/models/agent-config-audit.model.ts
new file mode 100644
index 0000000..603b557
--- /dev/null
+++ b/backend/src/models/agent-config-audit.model.ts
@@ -0,0 +1,28 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+
+const { Schema, model, models } = mongoose;
+
+export interface AgentConfigAuditDoc {
+  _id: ObjectId;
+  agentName: string;
+  actorId: string;
+  action: string;
+  before: unknown;
+  after: unknown;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+const agentConfigAuditSchema = new Schema<AgentConfigAuditDoc>(
+  {
+    agentName: { type: String, required: true },
+    actorId: { type: String, required: true },
+    action: { type: String, required: true },
+    before: { type: Schema.Types.Mixed },
+    after: { type: Schema.Types.Mixed },
+  },
+  { timestamps: true },
+);
+
+export const AgentConfigAudit = (models.AgentConfigAudit ?? model('AgentConfigAudit', agentConfigAuditSchema)) as Model<AgentConfigAuditDoc>;
\ No newline at end of file
diff --git a/backend/src/models/agent-config.model.ts b/backend/src/models/agent-config.model.ts
new file mode 100644
index 0000000..989e269
--- /dev/null
+++ b/backend/src/models/agent-config.model.ts
@@ -0,0 +1,48 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+import type { AgentConfig as AgentConfigDTO, TriageMode, WorkOrderPriority } from '@workorders/shared';
+
+const { Schema, model, models } = mongoose;
+
+export interface AgentConfigDoc {
+  _id: ObjectId;
+  name: string;
+  enabled: boolean;
+  mode: TriageMode;
+  allowedFields: string[];
+  dailyActionCap: number;
+  flagThreshold: WorkOrderPriority;
+  workingHours: string;
+  updatedBy: string | null;
+  updatedAt: Date;
+}
+
+const agentConfigSchema = new Schema<AgentConfigDoc>(
+  {
+    name: { type: String, required: true, unique: true, default: 'triage' },
+    enabled: { type: Boolean, default: true },
+    mode: { type: String, enum: ['suggest', 'auto-apply'], default: 'suggest' },
+    allowedFields: { type: [String], default: ['priority'] },
+    dailyActionCap: { type: Number, default: 50 },
+    flagThreshold: { type: String, enum: ['low', 'medium', 'high'], default: 'high' },
+    workingHours: { type: String, default: '*' },
+    updatedBy: { type: String, default: null },
+  },
+  { timestamps: true },
+);
+
+export const AgentConfig = (models.AgentConfig ?? model('AgentConfig', agentConfigSchema)) as Model<AgentConfigDoc>;
+
+export function toAgentConfigPublic(config: AgentConfigDoc): AgentConfigDTO {
+  return {
+    name: config.name,
+    enabled: config.enabled,
+    mode: config.mode,
+    allowedFields: config.allowedFields,
+    dailyActionCap: config.dailyActionCap,
+    flagThreshold: config.flagThreshold,
+    workingHours: config.workingHours,
+    updatedBy: config.updatedBy,
+    updatedAt: config.updatedAt.toISOString(),
+  };
+}
\ No newline at end of file
diff --git a/backend/src/models/agent-message.model.ts b/backend/src/models/agent-message.model.ts
new file mode 100644
index 0000000..16f034b
--- /dev/null
+++ b/backend/src/models/agent-message.model.ts
@@ -0,0 +1,34 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+
+const { Schema, model, models } = mongoose;
+
+export type AgentMessageRole = 'system' | 'user' | 'assistant' | 'tool';
+
+export interface AgentMessageDoc {
+  _id: ObjectId;
+  runId: ObjectId;
+  role: AgentMessageRole;
+  content: string;
+  toolCallId?: string;
+  name?: string;
+  expiresAt: Date | null;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+const agentMessageSchema = new Schema<AgentMessageDoc>(
+  {
+    runId: { type: Schema.ObjectId, ref: 'AgentRun', required: true, index: true },
+    role: { type: String, enum: ['system', 'user', 'assistant', 'tool'], required: true },
+    content: { type: String, required: true },
+    toolCallId: { type: String },
+    name: { type: String },
+    expiresAt: { type: Date, default: null },
+  },
+  { timestamps: true },
+);
+
+agentMessageSchema.index({ expiresAt: 1 }, { expireAfterSeconds: 0 });
+
+export const AgentMessage = (models.AgentMessage ?? model('AgentMessage', agentMessageSchema)) as Model<AgentMessageDoc>;
\ No newline at end of file
diff --git a/backend/src/models/agent-run.model.ts b/backend/src/models/agent-run.model.ts
new file mode 100644
index 0000000..b317220
--- /dev/null
+++ b/backend/src/models/agent-run.model.ts
@@ -0,0 +1,65 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+import type { AgentRun as AgentRunDTO, AgentRunMode, AgentRunStatus, ErrorCode } from '@workorders/shared';
+
+const { Schema, model, models } = mongoose;
+
+export interface AgentRunDoc {
+  _id: ObjectId;
+  sessionId: ObjectId | null;
+  userId: ObjectId | null;
+  mode: AgentRunMode;
+  agentName?: string;
+  status: AgentRunStatus;
+  model: string;
+  inputTokens: number;
+  outputTokens: number;
+  errorCode?: string;
+  finishedAt: Date | null;
+  leaseUntil: Date | null;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+const agentRunSchema = new Schema<AgentRunDoc>(
+  {
+    sessionId: { type: Schema.ObjectId, ref: 'CopilotSession', default: null },
+    userId: { type: Schema.ObjectId, ref: 'User', default: null },
+    mode: { type: String, enum: ['copilot', 'autonomous'], required: true },
+    agentName: { type: String },
+    status: {
+      type: String,
+      enum: ['running', 'complete', 'error', 'budget_exceeded', 'expired', 'aborted'],
+      default: 'running',
+    },
+    model: { type: String, required: true },
+    inputTokens: { type: Number, default: 0 },
+    outputTokens: { type: Number, default: 0 },
+    errorCode: { type: String },
+    finishedAt: { type: Date, default: null },
+    leaseUntil: { type: Date, default: null },
+  },
+  { timestamps: true },
+);
+
+agentRunSchema.index({ userId: 1, status: 1 });
+agentRunSchema.index({ sessionId: 1 });
+agentRunSchema.index({ status: 1, leaseUntil: 1 });
+
+export const AgentRun = (models.AgentRun ?? model('AgentRun', agentRunSchema)) as Model<AgentRunDoc>;
+
+export function toAgentRunPublic(run: AgentRunDoc): AgentRunDTO {
+  return {
+    id: run._id.toString(),
+    mode: run.mode,
+    actorId: run.userId ? run.userId.toString() : null,
+    ...(run.agentName ? { agentName: run.agentName } : {}),
+    status: run.status,
+    model: run.model,
+    inputTokens: run.inputTokens,
+    outputTokens: run.outputTokens,
+    startedAt: run.createdAt.toISOString(),
+    finishedAt: run.finishedAt ? run.finishedAt.toISOString() : null,
+    ...(run.errorCode ? { errorCode: run.errorCode as ErrorCode } : {}),
+  };
+}
\ No newline at end of file
diff --git a/backend/src/models/agent-spend.model.ts b/backend/src/models/agent-spend.model.ts
new file mode 100644
index 0000000..3c1e40d
--- /dev/null
+++ b/backend/src/models/agent-spend.model.ts
@@ -0,0 +1,22 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+
+const { Schema, model, models } = mongoose;
+
+export interface AgentSpendDoc {
+  _id: ObjectId;
+  key: string;
+  spentUsd: number;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+const agentSpendSchema = new Schema<AgentSpendDoc>(
+  {
+    key: { type: String, required: true, unique: true },
+    spentUsd: { type: Number, default: 0 },
+  },
+  { timestamps: true },
+);
+
+export const AgentSpend = (models.AgentSpend ?? model('AgentSpend', agentSpendSchema)) as Model<AgentSpendDoc>;
\ No newline at end of file
diff --git a/backend/src/models/agent-tool-call.model.ts b/backend/src/models/agent-tool-call.model.ts
new file mode 100644
index 0000000..0204c5b
--- /dev/null
+++ b/backend/src/models/agent-tool-call.model.ts
@@ -0,0 +1,88 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+import type { AgentApproval, AgentApprovalStatus, AgentToolCall as AgentToolCallDTO, AgentToolOutcome } from '@workorders/shared';
+
+const { Schema, model, models } = mongoose;
+
+export interface AgentToolCallApprovalDoc {
+  status: AgentApprovalStatus;
+  summary: string;
+  expiresAt: Date;
+  decidedBy?: string;
+  decidedAt?: Date;
+}
+
+export interface AgentToolCallDoc {
+  _id: ObjectId;
+  runId: ObjectId;
+  tool: string;
+  args: unknown;
+  result?: unknown;
+  outcome: AgentToolOutcome;
+  latencyMs: number;
+  stagedVersion?: number;
+  executedVersion?: number;
+  preImage?: unknown;
+  approval?: AgentToolCallApprovalDoc;
+  expiresAt: Date | null;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+const agentToolCallSchema = new Schema<AgentToolCallDoc>(
+  {
+    runId: { type: Schema.ObjectId, ref: 'AgentRun', required: true, index: true },
+    tool: { type: String, required: true },
+    args: { type: Schema.Types.Mixed, required: true },
+    result: { type: Schema.Types.Mixed },
+    outcome: {
+      type: String,
+      enum: ['executed', 'approved', 'rejected', 'expired', 'stale', 'error', 'blocked', 'aborted'],
+      required: true,
+    },
+    latencyMs: { type: Number, default: 0 },
+    stagedVersion: { type: Number },
+    executedVersion: { type: Number },
+    preImage: { type: Schema.Types.Mixed },
+    approval: {
+      status: { type: String, enum: ['pending', 'approved', 'rejected', 'expired', 'stale'], default: 'pending' },
+      summary: { type: String, required: true },
+      expiresAt: { type: Date, required: true },
+      decidedBy: { type: String },
+      decidedAt: { type: Date },
+    },
+    expiresAt: { type: Date, default: null },
+  },
+  { timestamps: true },
+);
+
+agentToolCallSchema.index({ expiresAt: 1 }, { expireAfterSeconds: 0 });
+
+export const AgentToolCall = (models.AgentToolCall ?? model('AgentToolCall', agentToolCallSchema)) as Model<AgentToolCallDoc>;
+
+export function toAgentToolCallPublic(call: AgentToolCallDoc): AgentToolCallDTO {
+  return {
+    id: call._id.toString(),
+    runId: call.runId.toString(),
+    tool: call.tool,
+    args: call.args,
+    outcome: call.outcome,
+    latencyMs: call.latencyMs,
+    createdAt: call.createdAt.toISOString(),
+    ...(call.result !== undefined ? { result: call.result } : {}),
+    ...(call.stagedVersion !== undefined ? { stagedVersion: call.stagedVersion } : {}),
+    ...(call.executedVersion !== undefined ? { executedVersion: call.executedVersion } : {}),
+    ...(call.preImage !== undefined ? { preImage: call.preImage } : {}),
+    ...(call.approval
+      ? {
+          approval: {
+            status: call.approval.status,
+            summary: call.approval.summary,
+            expiresAt: call.approval.expiresAt.toISOString(),
+            ...(call.approval.decidedBy !== undefined ? { decidedBy: call.approval.decidedBy } : {}),
+            ...(call.approval.decidedAt !== undefined ? { decidedAt: call.approval.decidedAt.toISOString() } : {}),
+          } satisfies AgentApproval,
+        }
+      : {}),
+  };
+}
\ No newline at end of file
diff --git a/backend/src/models/copilot-session.model.ts b/backend/src/models/copilot-session.model.ts
new file mode 100644
index 0000000..bf4ae40
--- /dev/null
+++ b/backend/src/models/copilot-session.model.ts
@@ -0,0 +1,35 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+import type { CopilotSession as CopilotSessionDTO, CopilotSessionStatus } from '@workorders/shared';
+
+const { Schema, model, models } = mongoose;
+
+export interface CopilotSessionDoc {
+  _id: ObjectId;
+  userId: ObjectId;
+  status: CopilotSessionStatus;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+const copilotSessionSchema = new Schema<CopilotSessionDoc>(
+  {
+    userId: { type: Schema.ObjectId, ref: 'User', required: true },
+    status: { type: String, enum: ['active', 'archived', 'expired'], default: 'active' },
+  },
+  { timestamps: true },
+);
+
+copilotSessionSchema.index({ userId: 1, status: 1 });
+
+export const CopilotSession = (models.CopilotSession ?? model('CopilotSession', copilotSessionSchema)) as Model<CopilotSessionDoc>;
+
+export function toCopilotSessionPublic(session: CopilotSessionDoc): CopilotSessionDTO {
+  return {
+    id: session._id.toString(),
+    userId: session.userId.toString(),
+    status: session.status,
+    createdAt: session.createdAt.toISOString(),
+    updatedAt: session.updatedAt.toISOString(),
+  };
+}
\ No newline at end of file
diff --git a/backend/src/models/outbox-event.model.ts b/backend/src/models/outbox-event.model.ts
new file mode 100644
index 0000000..5a337d1
--- /dev/null
+++ b/backend/src/models/outbox-event.model.ts
@@ -0,0 +1,35 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+
+const { Schema, model, models } = mongoose;
+
+export type OutboxEventStatus = 'pending' | 'processing' | 'done' | 'failed';
+
+export interface OutboxEventDoc {
+  _id: ObjectId;
+  type: string;
+  payloadRef: string;
+  status: OutboxEventStatus;
+  claimedAt: Date | null;
+  leasedUntil: Date | null;
+  attempts: number;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+const outboxEventSchema = new Schema<OutboxEventDoc>(
+  {
+    type: { type: String, required: true },
+    payloadRef: { type: String, required: true },
+    status: { type: String, enum: ['pending', 'processing', 'done', 'failed'], default: 'pending' },
+    claimedAt: { type: Date, default: null },
+    leasedUntil: { type: Date, default: null },
+    attempts: { type: Number, default: 0 },
+  },
+  { timestamps: true },
+);
+
+outboxEventSchema.index({ type: 1, payloadRef: 1 }, { unique: true });
+outboxEventSchema.index({ status: 1, leasedUntil: 1 });
+
+export const OutboxEvent = (models.OutboxEvent ?? model('OutboxEvent', outboxEventSchema)) as Model<OutboxEventDoc>;
\ No newline at end of file
diff --git a/backend/src/models/triage-suggestion.model.ts b/backend/src/models/triage-suggestion.model.ts
new file mode 100644
index 0000000..530001a
--- /dev/null
+++ b/backend/src/models/triage-suggestion.model.ts
@@ -0,0 +1,44 @@
+import mongoose from 'mongoose';
+import type { Model, ObjectId } from 'mongoose';
+import type { TriageSuggestion as TriageSuggestionDTO, WorkOrderPriority } from '@workorders/shared';
+
+const { Schema, model, models } = mongoose;
+
+export interface TriageSuggestionDoc {
+  _id: ObjectId;
+  workOrderId: ObjectId;
+  runId: ObjectId;
+  summary: string;
+  suggestedPriority: WorkOrderPriority;
+  flagForDispatcher: boolean;
+  applied: boolean;
+  createdAt: Date;
+  updatedAt: Date;
+}
+
+const triageSuggestionSchema = new Schema<TriageSuggestionDoc>(
+  {
+    workOrderId: { type: Schema.ObjectId, ref: 'WorkOrder', required: true, index: true },
+    runId: { type: Schema.ObjectId, ref: 'AgentRun', required: true },
+    summary: { type: String, required: true },
+    suggestedPriority: { type: String, enum: ['low', 'medium', 'high'], required: true },
+    flagForDispatcher: { type: Boolean, default: false },
+    applied: { type: Boolean, default: false },
+  },
+  { timestamps: true },
+);
+
+export const TriageSuggestion = (models.TriageSuggestion ?? model('TriageSuggestion', triageSuggestionSchema)) as Model<TriageSuggestionDoc>;
+
+export function toTriageSuggestionPublic(suggestion: TriageSuggestionDoc): TriageSuggestionDTO {
+  return {
+    id: suggestion._id.toString(),
+    workOrderId: suggestion.workOrderId.toString(),
+    runId: suggestion.runId.toString(),
+    summary: suggestion.summary,
+    suggestedPriority: suggestion.suggestedPriority,
+    flagForDispatcher: suggestion.flagForDispatcher,
+    applied: suggestion.applied,
+    createdAt: suggestion.createdAt.toISOString(),
+  };
+}
\ No newline at end of file
diff --git a/backend/src/models/user.model.ts b/backend/src/models/user.model.ts
index 2be817e..3a98b07 100644
--- a/backend/src/models/user.model.ts
+++ b/backend/src/models/user.model.ts
@@ -11,6 +11,7 @@ export interface UserDoc {
   name: string;
   role: Role;
   isActive: boolean;
+  aiEnabled: boolean;
   lastLoginAt: Date | null;
   failedLoginCount: number;
   failedLoginWindowStartAt: Date | null;
@@ -30,6 +31,7 @@ const userSchema = new Schema<UserDoc>(
     name: { type: String, required: true },
     role: { type: String, enum: ['admin', 'user', 'viewer'], default: 'user' },
     isActive: { type: Boolean, default: true },
+    aiEnabled: { type: Boolean, default: true },
     lastLoginAt: { type: Date, default: null },
     failedLoginCount: { type: Number, default: 0 },
     failedLoginWindowStartAt: { type: Date, default: null },
@@ -62,6 +64,7 @@ export function toUserAdmin(user: UserDoc): UserAdmin {
   return {
     ...toUserPublic(user),
     isActive: user.isActive,
+    aiEnabled: user.aiEnabled,
     lastLoginAt: user.lastLoginAt ? user.lastLoginAt.toISOString() : null,
   };
 }
\ No newline at end of file
diff --git a/backend/src/repositories/agent.repo.ts b/backend/src/repositories/agent.repo.ts
new file mode 100644
index 0000000..96dfd15
--- /dev/null
+++ b/backend/src/repositories/agent.repo.ts
@@ -0,0 +1,287 @@
+import type {
+  AgentApprovalStatus,
+  AgentRunMode,
+  AgentRunStatus,
+  AgentToolOutcome,
+  CopilotSessionStatus,
+  WorkOrderPriority,
+} from '@workorders/shared';
+import { CopilotSession, type CopilotSessionDoc } from '../models/copilot-session.model.js';
+import { AgentRun, type AgentRunDoc } from '../models/agent-run.model.js';
+import { AgentMessage, type AgentMessageDoc } from '../models/agent-message.model.js';
+import { AgentToolCall, type AgentToolCallDoc } from '../models/agent-tool-call.model.js';
+import { OutboxEvent, type OutboxEventDoc } from '../models/outbox-event.model.js';
+import { TriageSuggestion, type TriageSuggestionDoc } from '../models/triage-suggestion.model.js';
+import { AgentConfig, type AgentConfigDoc } from '../models/agent-config.model.js';
+import { AgentConfigAudit } from '../models/agent-config-audit.model.js';
+import { AgentSpend } from '../models/agent-spend.model.js';
+
+const TTL_MS = 90 * 24 * 60 * 60 * 1000;
+
+export const agentRepo = {
+  async createSession(userId: string): Promise<CopilotSessionDoc> {
+    return CopilotSession.create({ userId });
+  },
+
+  async findSessionById(id: string): Promise<CopilotSessionDoc | null> {
+    return CopilotSession.findById(id).lean();
+  },
+
+  async listSessionsForUser(userId: string): Promise<CopilotSessionDoc[]> {
+    return CopilotSession.find({ userId }).sort({ createdAt: -1 }).lean();
+  },
+
+  async archiveSession(id: string): Promise<void> {
+    await CopilotSession.updateOne({ _id: id }, { $set: { status: 'archived' } });
+  },
+
+  async setSessionStatus(id: string, status: CopilotSessionStatus): Promise<void> {
+    await CopilotSession.updateOne({ _id: id }, { $set: { status } });
+  },
+
+  async createRun(input: {
+    sessionId: string;
+    userId: string;
+    mode: AgentRunMode;
+    agentName?: string;
+    model: string;
+  }): Promise<AgentRunDoc> {
+    return AgentRun.create({
+      sessionId: input.sessionId,
+      userId: input.userId,
+      mode: input.mode,
+      agentName: input.agentName,
+      model: input.model,
+    });
+  },
+
+  async findRunById(id: string): Promise<AgentRunDoc | null> {
+    return AgentRun.findById(id).lean();
+  },
+
+  async finishRun(
+    id: string,
+    patch: { status: AgentRunStatus; finishedAt: Date; errorCode?: string; inputTokens?: number; outputTokens?: number },
+  ): Promise<void> {
+    const set: Record<string, unknown> = { status: patch.status, finishedAt: patch.finishedAt };
+    if (patch.errorCode !== undefined) set.errorCode = patch.errorCode;
+    if (patch.inputTokens !== undefined) set.inputTokens = patch.inputTokens;
+    if (patch.outputTokens !== undefined) set.outputTokens = patch.outputTokens;
+    await AgentRun.updateOne({ _id: id }, { $set: set });
+  },
+
+  async hasNonTerminalRun(sessionId: string): Promise<boolean> {
+    return (await AgentRun.exists({ sessionId, status: 'running' })) !== null;
+  },
+
+  async listRunsForUser(userId: string): Promise<AgentRunDoc[]> {
+    return AgentRun.find({ userId }).sort({ createdAt: -1 }).lean();
+  },
+
+  async listAdminRuns(page: number, limit: number): Promise<{ items: AgentRunDoc[]; page: number; limit: number; total: number }> {
+    const total = await AgentRun.countDocuments();
+    const items = await AgentRun.find()
+      .sort({ createdAt: -1 })
+      .skip((page - 1) * limit)
+      .limit(limit)
+      .lean();
+    return { items, page, limit, total };
+  },
+
+  async listNonTerminalRuns(): Promise<AgentRunDoc[]> {
+    return AgentRun.find({ status: 'running' }).sort({ createdAt: 1 }).lean();
+  },
+
+  async markStaleRuns(olderThan: Date): Promise<void> {
+    await AgentRun.updateMany(
+      { status: 'running', leaseUntil: { $lt: olderThan } },
+      { $set: { status: 'error', finishedAt: new Date() } },
+    );
+  },
+
+  async addSpendToRun(runId: string, inputTokens: number, outputTokens: number): Promise<void> {
+    await AgentRun.updateOne({ _id: runId }, { $inc: { inputTokens, outputTokens } });
+  },
+
+  async addMessage(
+    runId: string,
+    role: 'system' | 'user' | 'assistant' | 'tool',
+    content: string,
+    extra?: { toolCallId?: string; name?: string },
+  ): Promise<void> {
+    await AgentMessage.create({
+      runId,
+      role,
+      content,
+      toolCallId: extra?.toolCallId,
+      name: extra?.name,
+      expiresAt: new Date(Date.now() + TTL_MS),
+    });
+  },
+
+  async listMessages(runId: string): Promise<AgentMessageDoc[]> {
+    return AgentMessage.find({ runId }).sort({ createdAt: 1 }).lean();
+  },
+
+  async createToolCall(input: {
+    runId: string;
+    tool: string;
+    args: unknown;
+    outcome: AgentToolOutcome;
+    latencyMs: number;
+    result?: unknown;
+    stagedVersion?: number;
+    executedVersion?: number;
+    preImage?: unknown;
+    approval?: { status: AgentApprovalStatus; summary: string; expiresAt: Date };
+  }): Promise<AgentToolCallDoc> {
+    return AgentToolCall.create({
+      runId: input.runId,
+      tool: input.tool,
+      args: input.args,
+      outcome: input.outcome,
+      latencyMs: input.latencyMs,
+      result: input.result,
+      stagedVersion: input.stagedVersion,
+      executedVersion: input.executedVersion,
+      preImage: input.preImage,
+      approval: input.approval,
+      expiresAt: new Date(Date.now() + TTL_MS),
+    });
+  },
+
+  async findToolCallById(id: string): Promise<AgentToolCallDoc | null> {
+    return AgentToolCall.findById(id).lean();
+  },
+
+  async resolveToolCallApproval(
+    id: string,
+    decision: { status: 'approved' | 'rejected'; decidedBy: string },
+  ): Promise<AgentToolCallDoc | null> {
+    return AgentToolCall.findOneAndUpdate(
+      { _id: id, 'approval.status': 'pending' },
+      {
+        $set: {
+          'approval.status': decision.status,
+          'approval.decidedBy': decision.decidedBy,
+          'approval.decidedAt': new Date(),
+        },
+      },
+      { new: true },
+    ).lean();
+  },
+
+  async expireToolCallApproval(id: string): Promise<void> {
+    await AgentToolCall.updateOne({ _id: id, 'approval.status': 'pending' }, { $set: { 'approval.status': 'expired' } });
+  },
+
+  async expireApprovalsForRuns(runIds: string[]): Promise<void> {
+    await AgentToolCall.updateMany(
+      { runId: { $in: runIds }, 'approval.status': 'pending' },
+      { $set: { 'approval.status': 'expired' } },
+    );
+  },
+
+  async listToolCallsForRun(runId: string): Promise<AgentToolCallDoc[]> {
+    return AgentToolCall.find({ runId }).sort({ createdAt: 1 }).lean();
+  },
+
+  async chargeSpend(key: string, usd: number): Promise<number> {
+    const doc = await AgentSpend.findOneAndUpdate({ key }, { $inc: { spentUsd: usd } }, { upsert: true, new: true }).lean();
+    return doc ? doc.spentUsd : usd;
+  },
+
+  async getSpend(key: string): Promise<number> {
+    const doc = await AgentSpend.findOne({ key }).lean();
+    return doc?.spentUsd ?? 0;
+  },
+
+  async enqueueOutbox(input: { type: string; payloadRef: string }): Promise<void> {
+    await OutboxEvent.updateOne(
+      { type: input.type, payloadRef: input.payloadRef },
+      { $setOnInsert: { status: 'pending', attempts: 0 } },
+      { upsert: true },
+    );
+  },
+
+  async claimOutboxEvent(now: Date, leaseMs: number): Promise<OutboxEventDoc | null> {
+    return OutboxEvent.findOneAndUpdate(
+      {
+        $or: [{ status: 'pending' }, { status: 'processing', leasedUntil: { $lt: now } }],
+      },
+      {
+        $set: { status: 'processing', claimedAt: now, leasedUntil: new Date(now.getTime() + leaseMs) },
+        $inc: { attempts: 1 },
+      },
+      { sort: { createdAt: 1 }, new: true },
+    ).lean();
+  },
+
+  async completeOutbox(id: string): Promise<void> {
+    await OutboxEvent.updateOne({ _id: id }, { $set: { status: 'done' } });
+  },
+
+  async failOutbox(id: string): Promise<void> {
+    await OutboxEvent.updateOne({ _id: id }, { $set: { status: 'failed' } });
+  },
+
+  async listPendingOutboxEvents(): Promise<OutboxEventDoc[]> {
+    const now = new Date();
+    return OutboxEvent.find({
+      $or: [{ status: 'pending' }, { status: 'processing', leasedUntil: { $lt: now } }],
+    })
+      .sort({ createdAt: 1 })
+      .lean();
+  },
+
+  async markOutboxDoneForPayload(type: string, payloadRef: string): Promise<void> {
+    await OutboxEvent.updateOne({ type, payloadRef }, { $set: { status: 'done' } });
+  },
+
+  async createSuggestion(input: {
+    workOrderId: string;
+    runId: string;
+    summary: string;
+    suggestedPriority: WorkOrderPriority;
+    flagForDispatcher: boolean;
+    applied: boolean;
+  }): Promise<TriageSuggestionDoc> {
+    return TriageSuggestion.create(input);
+  },
+
+  async listSuggestionsForWorkOrder(workOrderId: string): Promise<TriageSuggestionDoc[]> {
+    return TriageSuggestion.find({ workOrderId }).sort({ createdAt: -1 }).lean();
+  },
+
+  async countSuggestionsToday(): Promise<number> {
+    const start = new Date();
+    start.setHours(0, 0, 0, 0);
+    return TriageSuggestion.countDocuments({ createdAt: { $gte: start } });
+  },
+
+  async getAgentConfig(name = 'triage'): Promise<AgentConfigDoc | null> {
+    return AgentConfig.findOne({ name }).lean();
+  },
+
+  async upsertAgentConfig(name = 'triage'): Promise<AgentConfigDoc> {
+    const doc = await AgentConfig.findOneAndUpdate({ name }, { $setOnInsert: { name } }, { upsert: true, new: true }).lean();
+    if (!doc) throw new Error('Failed to upsert agent config');
+    return doc;
+  },
+
+  async updateAgentConfig(
+    name: string,
+    patch: Partial<Pick<AgentConfigDoc, 'mode' | 'allowedFields' | 'dailyActionCap' | 'flagThreshold' | 'workingHours'>>,
+    updatedBy: string,
+  ): Promise<AgentConfigDoc | null> {
+    return AgentConfig.findOneAndUpdate({ name }, { $set: { ...patch, updatedBy } }, { new: true }).lean();
+  },
+
+  async setAgentEnabled(enabled: boolean, updatedBy: string): Promise<AgentConfigDoc | null> {
+    return AgentConfig.findOneAndUpdate({ name: 'triage' }, { $set: { enabled, updatedBy } }, { new: true }).lean();
+  },
+
+  async appendConfigAudit(input: { agentName: string; actorId: string; action: string; before: unknown; after: unknown }): Promise<void> {
+    await AgentConfigAudit.create(input);
+  },
+};
\ No newline at end of file
diff --git a/backend/src/repositories/user.repo.ts b/backend/src/repositories/user.repo.ts
index 773c61e..d914718 100644
--- a/backend/src/repositories/user.repo.ts
+++ b/backend/src/repositories/user.repo.ts
@@ -122,6 +122,10 @@ export const userRepo = {
     return User.findByIdAndUpdate(id, { $set: { isActive } }, { new: true }).lean();
   },
 
+  async updateAiEnabled(id: string, aiEnabled: boolean): Promise<UserDoc | null> {
+    return User.findByIdAndUpdate(id, { $set: { aiEnabled } }, { new: true }).lean();
+  },
+
   async updateName(id: string, name: string): Promise<UserDoc | null> {
     return User.findByIdAndUpdate(id, { $set: { name } }, { new: true }).lean();
   },
diff --git a/backend/src/repositories/work-order.repo.ts b/backend/src/repositories/work-order.repo.ts
index 8566be4..0be1aab 100644
--- a/backend/src/repositories/work-order.repo.ts
+++ b/backend/src/repositories/work-order.repo.ts
@@ -1,4 +1,5 @@
 import type { WorkOrderPriority, WorkOrderStatus } from '@workorders/shared';
+import { agentRepo } from './agent.repo.js';
 import { WorkOrder, type WorkOrderDoc } from '../models/work-order.model.js';
 import { signCursor, verifyCursor, type CursorPayload } from '../utils/cursor.js';
 import { validation } from '../utils/http-error.js';
@@ -74,7 +75,7 @@ export const workOrderRepo = {
     priority: WorkOrderPriority;
     status: WorkOrderStatus;
   }): Promise<WorkOrderDoc> {
-    return WorkOrder.create({
+    const doc = await WorkOrder.create({
       owner: input.ownerId,
       title: input.title,
       description: input.description ?? null,
@@ -82,6 +83,8 @@ export const workOrderRepo = {
       status: input.status,
       version: 1,
     });
+    await agentRepo.enqueueOutbox({ type: 'work_order.created', payloadRef: doc._id.toString() });
+    return doc;
   },
 
   async findById(id: string): Promise<WorkOrderDoc | null> {
diff --git a/backend/src/services/admin.service.ts b/backend/src/services/admin.service.ts
index a005250..27594cc 100644
--- a/backend/src/services/admin.service.ts
+++ b/backend/src/services/admin.service.ts
@@ -64,4 +64,14 @@ export const adminService = {
     const [users, workOrders] = await Promise.all([userRepo.countAll(), workOrderRepo.countAll()]);
     return { users, workOrders, uptimeSeconds: Math.floor(process.uptime()) };
   },
+
+  async updateAiEnabled(adminId: string, targetId: string, aiEnabled: boolean): Promise<UserAdmin> {
+    assertValidObjectId(targetId, 'id');
+    if (targetId === adminId) throw forbidden('Cannot change your own AI access');
+    const target = await userRepo.findById(targetId);
+    if (!target) throw notFound();
+    const updated = await userRepo.updateAiEnabled(targetId, aiEnabled);
+    if (!updated) throw notFound();
+    return toUserAdmin(updated);
+  },
 };
\ No newline at end of file
diff --git a/backend/src/services/work-order.service.ts b/backend/src/services/work-order.service.ts
index 2ff8734..18cca14 100644
--- a/backend/src/services/work-order.service.ts
+++ b/backend/src/services/work-order.service.ts
@@ -1,9 +1,9 @@
-import type { WorkOrderPublic } from '@workorders/shared';
+import type { WorkOrderPriority, WorkOrderPublic } from '@workorders/shared';
 import { workOrderRepo, type WorkOrderListQuery } from '../repositories/work-order.repo.js';
 import { toWorkOrderPublicWithOwner } from '../models/work-order.model.js';
-import type { Actor } from '../utils/actor.js';
+import { isSystemActor, type Actor } from '../utils/actor.js';
 import { assertValidObjectId } from '../utils/object-id.js';
-import { conflictVersion, forbidden, notFound } from '../utils/http-error.js';
+import { conflictVersion, forbidden, notFound, validation } from '../utils/http-error.js';
 
 export interface WorkOrderListResult {
   items: WorkOrderPublic[];
@@ -34,6 +34,7 @@ export const workOrderService = {
   },
 
   async get(actor: Actor, id: string): Promise<WorkOrderPublic> {
+    if (isSystemActor(actor)) throw forbidden('System actors cannot use this endpoint');
     assertValidObjectId(id);
     const wo = await workOrderRepo.findById(id);
     if (!wo) throw notFound();
@@ -52,6 +53,7 @@ export const workOrderService = {
       version: number;
     },
   ): Promise<WorkOrderPublic> {
+    if (isSystemActor(actor)) throw forbidden('System actors cannot use this endpoint');
     assertWritable(actor);
     assertValidObjectId(id);
     const existing = await workOrderRepo.findById(id);
@@ -79,6 +81,7 @@ export const workOrderService = {
   },
 
   async remove(actor: Actor, id: string, version: number): Promise<void> {
+    if (isSystemActor(actor)) throw forbidden('System actors cannot use this endpoint');
     assertWritable(actor);
     assertValidObjectId(id);
     const existing = await workOrderRepo.findByIdIncludingDeleted(id);
@@ -98,6 +101,26 @@ export const workOrderService = {
       throw conflictVersion();
     }
   },
+
+  async triagePatch(actor: Actor, id: string, input: { priority?: WorkOrderPriority }): Promise<WorkOrderPublic> {
+    if (!isSystemActor(actor) || actor.capability !== 'triage') throw forbidden('Triage capability required');
+    assertValidObjectId(id);
+    if (input.priority === undefined) throw validation([{ field: 'priority', message: 'priority is required' }]);
+    const existing = await workOrderRepo.findByIdIncludingDeleted(id);
+    if (!existing) throw notFound();
+    if (existing.deletedAt) throw notFound();
+    const updated = await workOrderRepo.updateIfVersion({
+      id,
+      version: existing.version,
+      patch: { priority: input.priority },
+    });
+    if (!updated) {
+      const current = await workOrderRepo.findByIdIncludingDeleted(id);
+      if (!current || current.deletedAt) throw notFound();
+      throw conflictVersion();
+    }
+    return toWorkOrderPublicWithOwner(updated);
+  },
 };
 
 function assertWritable(actor: Actor): void {
diff --git a/backend/src/utils/actor.ts b/backend/src/utils/actor.ts
index 8addb46..d76124b 100644
--- a/backend/src/utils/actor.ts
+++ b/backend/src/utils/actor.ts
@@ -1,6 +1,18 @@
 import type { Role } from '@workorders/shared';
 
+export type ActorKind = 'human' | 'system';
+
 export interface Actor {
   id: string;
   role: Role;
+  kind: ActorKind;
+  capability?: 'triage';
+}
+
+export function systemActor(capability: 'triage'): Actor {
+  return { id: 'system', role: 'user', kind: 'system', capability };
+}
+
+export function isSystemActor(actor: Actor): boolean {
+  return actor.kind === 'system';
 }
\ No newline at end of file