diff --git a/packages/iios-service/src/adapters/adapters.controller.ts b/packages/iios-service/src/adapters/adapters.controller.ts
index 1a24b83..e23a58d 100644
--- a/packages/iios-service/src/adapters/adapters.controller.ts
+++ b/packages/iios-service/src/adapters/adapters.controller.ts
@@ -1,10 +1,19 @@
-import { Controller, HttpCode, Param, Post, Req } from '@nestjs/common';
+import { BadRequestException, Body, Controller, Get, Headers, HttpCode, Param, Post, Req } from '@nestjs/common';
 import type { Request } from 'express';
 import { InboundService } from './inbound.service';
+import { OutboundService } from './outbound.service';
+import { SessionVerifier } from '../platform/session.verifier';
+import { PrismaService } from '../prisma/prisma.service';
+import { SendDto } from './adapters.dto';
 
 @Controller('v1/adapters')
 export class AdaptersController {
-  constructor(private readonly inbound: InboundService) {}
+  constructor(
+    private readonly inbound: InboundService,
+    private readonly outbound: OutboundService,
+    private readonly session: SessionVerifier,
+    private readonly prisma: PrismaService,
+  ) {}
 
   /** Provider webhook. Authenticated by HMAC signature (not a session token). */
   @Post(':channelType/webhook')
@@ -14,4 +23,30 @@ export class AdaptersController {
     const headers = req.headers as Record<string, string | undefined>;
     return this.inbound.receive(channelType, rawBody, headers);
   }
+
+  /** Outbound to the sandbox sink (session-auth). No real network. */
+  @Post(':channelType/send')
+  async send(@Param('channelType') channelType: string, @Body() body: SendDto, @Headers('authorization') auth?: string) {
+    this.requireSession(auth);
+    return this.outbound.send(channelType, body.target, body.payload ?? {}, body.idempotencyKey);
+  }
+
+  // ─── inspector reads (session-auth) ───────────────────────────────
+  @Get('inbound')
+  async listInbound(@Headers('authorization') auth?: string) {
+    this.requireSession(auth);
+    return this.prisma.iiosInboundRawEvent.findMany({ orderBy: { createdAt: 'desc' }, take: 50 });
+  }
+
+  @Get('outbound')
+  async listOutbound(@Headers('authorization') auth?: string) {
+    this.requireSession(auth);
+    return this.prisma.iiosOutboundCommand.findMany({ orderBy: { createdAt: 'desc' }, take: 50, include: { attempts: true } });
+  }
+
+  private requireSession(authorization?: string): void {
+    const token = (authorization ?? '').replace(/^Bearer\s+/i, '');
+    if (!token) throw new BadRequestException('Authorization bearer token is required');
+    this.session.verify(token);
+  }
 }
diff --git a/packages/iios-service/src/adapters/adapters.dto.ts b/packages/iios-service/src/adapters/adapters.dto.ts
new file mode 100644
index 0000000..c82bab7
--- /dev/null
+++ b/packages/iios-service/src/adapters/adapters.dto.ts
@@ -0,0 +1,7 @@
+import { IsObject, IsOptional, IsString } from 'class-validator';
+
+export class SendDto {
+  @IsString() target!: string;
+  @IsOptional() @IsObject() payload?: Record<string, unknown>;
+  @IsOptional() @IsString() idempotencyKey?: string;
+}
diff --git a/packages/iios-service/src/adapters/adapters.module.ts b/packages/iios-service/src/adapters/adapters.module.ts
index bf5e0c0..71b3900 100644
--- a/packages/iios-service/src/adapters/adapters.module.ts
+++ b/packages/iios-service/src/adapters/adapters.module.ts
@@ -3,13 +3,14 @@ import { OutboxModule } from '../outbox/outbox.module';
 import { InteractionsModule } from '../interactions/interactions.module';
 import { AdapterRegistry } from './adapter.registry';
 import { InboundService } from './inbound.service';
+import { OutboundService } from './outbound.service';
 import { RawEventProjector } from './raw-event.projector';
 import { AdaptersController } from './adapters.controller';
 
 @Module({
   imports: [OutboxModule, InteractionsModule],
   controllers: [AdaptersController],
-  providers: [AdapterRegistry, InboundService, RawEventProjector],
-  exports: [AdapterRegistry, InboundService],
+  providers: [AdapterRegistry, InboundService, OutboundService, RawEventProjector],
+  exports: [AdapterRegistry, InboundService, OutboundService],
 })
 export class AdaptersModule {}
diff --git a/packages/iios-service/src/adapters/adapters.spec.ts b/packages/iios-service/src/adapters/adapters.spec.ts
index 0130881..3abe49b 100644
--- a/packages/iios-service/src/adapters/adapters.spec.ts
+++ b/packages/iios-service/src/adapters/adapters.spec.ts
@@ -6,6 +6,7 @@ import { IIOS_EVENTS, type CloudEvent } from '@insignia/iios-contracts';
 import { signedFixture, emailFixture } from '@insignia/iios-adapter-sdk';
 import { AdapterRegistry } from './adapter.registry';
 import { InboundService } from './inbound.service';
+import { OutboundService } from './outbound.service';
 import { RawEventProjector } from './raw-event.projector';
 import { IngestService } from '../interactions/ingest.service';
 import { ActorResolver } from '../identity/actor.resolver';
@@ -73,3 +74,34 @@ describe('Adapter inbound (P5)', () => {
     expect(await prisma.iiosInteraction.count()).toBe(1);
   });
 });
+
+describe('Adapter outbound (P5)', () => {
+  const outbound = (limit?: number): OutboundService => {
+    const s = new OutboundService(asService, registry());
+    if (limit) s.limit = limit;
+    return s;
+  };
+
+  it('send → command SENT + one delivery attempt (sandbox, no network)', async () => {
+    const cmd = await outbound().send('WEBHOOK', 'user@x', { text: 'hi' }, 'ob-1');
+    expect(cmd.status).toBe('SENT');
+    expect(cmd.providerRef).toContain('sim-');
+    expect(await prisma.iiosDeliveryAttempt.count({ where: { commandId: cmd.id } })).toBe(1);
+  });
+
+  it('rate limit: exceeding the window → RATE_LIMITED', async () => {
+    const svc = outbound(2);
+    await svc.send('WEBHOOK', 't', {}, 'a');
+    await svc.send('WEBHOOK', 't', {}, 'b');
+    const third = await svc.send('WEBHOOK', 't', {}, 'c');
+    expect(third.status).toBe('RATE_LIMITED');
+  });
+
+  it('idempotent: same key twice → one command', async () => {
+    const svc = outbound();
+    const a = await svc.send('WEBHOOK', 't2', {}, 'k');
+    const b = await svc.send('WEBHOOK', 't2', {}, 'k');
+    expect(b.id).toBe(a.id);
+    expect(await prisma.iiosOutboundCommand.count()).toBe(1);
+  });
+});
diff --git a/packages/iios-service/src/adapters/outbound.service.ts b/packages/iios-service/src/adapters/outbound.service.ts
new file mode 100644
index 0000000..c5f319e
--- /dev/null
+++ b/packages/iios-service/src/adapters/outbound.service.ts
@@ -0,0 +1,73 @@
+import { randomUUID } from 'node:crypto';
+import { Injectable, NotFoundException } from '@nestjs/common';
+import { Prisma } from '@prisma/client';
+import { PrismaService } from '../prisma/prisma.service';
+import { AdapterRegistry } from './adapter.registry';
+
+/**
+ * Outbound to a provider — in P5 the adapter's `send` is a SANDBOX sink (no real
+ * network). Per-(channelType,target) rate limiting; idempotent per command key;
+ * every attempt recorded. Real delivery is gated to P6+.
+ */
+@Injectable()
+export class OutboundService {
+  /** Public so tests can lower them; default from env. */
+  limit = Number(process.env.IIOS_OUTBOUND_LIMIT ?? 5);
+  windowMs = Number(process.env.IIOS_OUTBOUND_WINDOW_MS ?? 60_000);
+
+  constructor(
+    private readonly prisma: PrismaService,
+    private readonly registry: AdapterRegistry,
+  ) {}
+
+  async send(
+    channelType: string,
+    target: string,
+    payload: Record<string, unknown>,
+    idempotencyKey: string = randomUUID(),
+  ) {
+    const reg = this.registry.get(channelType);
+    if (!reg) throw new NotFoundException(`unknown channel type: ${channelType}`);
+
+    const existing = await this.prisma.iiosOutboundCommand.findUnique({ where: { idempotencyKey } });
+    if (existing) return existing;
+
+    if (!(await this.allow(channelType, target))) {
+      const cmd = await this.prisma.iiosOutboundCommand.create({
+        data: { channelType, target, payload: payload as Prisma.InputJsonValue, status: 'RATE_LIMITED', idempotencyKey },
+      });
+      await this.prisma.iiosDeliveryAttempt.create({ data: { commandId: cmd.id, attemptNo: 1, status: 'RATE_LIMITED' } });
+      return cmd;
+    }
+
+    const cmd = await this.prisma.iiosOutboundCommand.create({
+      data: { channelType, target, payload: payload as Prisma.InputJsonValue, status: 'PENDING', idempotencyKey },
+    });
+    const result = await reg.adapter.send({ channelType, target, payload }); // sandbox — no network
+    const [updated] = await this.prisma.$transaction([
+      this.prisma.iiosOutboundCommand.update({ where: { id: cmd.id }, data: { status: 'SENT', providerRef: result.providerRef } }),
+      this.prisma.iiosDeliveryAttempt.create({
+        data: { commandId: cmd.id, attemptNo: 1, status: 'SENT', providerRef: result.providerRef, latencyMs: result.latencyMs },
+      }),
+    ]);
+    return updated;
+  }
+
+  /** Token/window bucket keyed by (channelType, target). Resets when the window elapses. */
+  private async allow(channelType: string, target: string): Promise<boolean> {
+    const now = new Date();
+    const where = { channelType_bucketKey: { channelType, bucketKey: target } };
+    const bucket = await this.prisma.iiosRateLimitBucket.findUnique({ where });
+    if (!bucket || bucket.resetAt <= now) {
+      await this.prisma.iiosRateLimitBucket.upsert({
+        where,
+        create: { channelType, bucketKey: target, windowStart: now, count: 1, resetAt: new Date(now.getTime() + this.windowMs) },
+        update: { windowStart: now, count: 1, resetAt: new Date(now.getTime() + this.windowMs) },
+      });
+      return true;
+    }
+    if (bucket.count >= this.limit) return false;
+    await this.prisma.iiosRateLimitBucket.update({ where, data: { count: { increment: 1 } } });
+    return true;
+  }
+}