Official TypeScript/JavaScript client for the Ad Context Protocol (AdCP). Build distributed advertising operations that work synchronously OR asynchronously with the same code.
AdCP operations are distributed and asynchronous by default. An agent might:
- Complete your request immediately (synchronous)
- Need time to process and send results via webhook (asynchronous)
- Ask for clarifications before proceeding
- Send periodic status updates as work progresses
Your code stays the same. You write handlers once, and they work for both sync completions and webhook deliveries.
npm install @adcp/clientimport { ADCPMultiAgentClient } from '@adcp/client';
// Configure agents and handlers
const client = new ADCPMultiAgentClient([
{
id: 'agent_x',
agent_uri: 'https://agent-x.com',
protocol: 'a2a'
},
{
id: 'agent_y',
agent_uri: 'https://agent-y.com/mcp/',
protocol: 'mcp'
}
], {
// Webhook URL template (macros: {agent_id}, {task_type}, {operation_id})
webhookUrlTemplate: 'https://myapp.com/webhook/{task_type}/{agent_id}/{operation_id}',
// Activity callback - fires for ALL events (requests, responses, status changes, webhooks)
onActivity: (activity) => {
console.log(`[${activity.type}] ${activity.task_type} - ${activity.operation_id}`);
// Log to monitoring, update UI, etc.
},
// Status change handlers - called for ALL status changes (completed, failed, needs_input, working, etc)
handlers: {
onGetProductsStatusChange: (response, metadata) => {
// Called for sync completion, async webhook, AND status changes
console.log(`[${metadata.status}] Got products for ${metadata.operation_id}`);
if (metadata.status === 'completed') {
db.saveProducts(metadata.operation_id, response.products);
} else if (metadata.status === 'failed') {
db.markFailed(metadata.operation_id, metadata.error);
} else if (metadata.status === 'needs_input') {
// Handle clarification needed
console.log('Needs input:', response.message);
}
}
}
});
// Execute operation - library handles operation IDs, webhook URLs, context management
const agent = client.agent('agent_x');
const result = await agent.getProducts({ brief: 'Coffee brands' });
// onActivity fired: protocol_request
// onActivity fired: protocol_response
// Check result
if (result.status === 'completed') {
// Agent completed synchronously!
console.log('✅ Sync completion:', result.data.products.length, 'products');
// onGetProductsStatusChange handler ALREADY fired with status='completed' ✓
}
if (result.status === 'submitted') {
// Agent will send webhook when complete
console.log('⏳ Async - webhook registered at:', result.submitted?.webhookUrl);
// onGetProductsStatusChange handler will fire when webhook arrives ✓
}When an agent needs more information, you can continue the conversation:
const result = await agent.getProducts({ brief: 'Coffee brands' });
if (result.status === 'needs_input') {
console.log('❓ Agent needs clarification:', result.needs_input?.message);
// onActivity fired: status_change (needs_input)
// Continue the conversation with the same agent
const refined = await agent.continueConversation('Only premium brands above $50');
// onActivity fired: protocol_request
// onActivity fired: protocol_response
if (refined.status === 'completed') {
console.log('✅ Got refined results:', refined.data.products.length);
// onGetProductsStatusChange handler fired ✓
}
}All webhooks (task completions AND notifications) use one endpoint with flexible URL templates.
const client = new ADCPMultiAgentClient(agents, {
// Path-based (default pattern)
webhookUrlTemplate: 'https://myapp.com/webhook/{task_type}/{agent_id}/{operation_id}',
// OR query string
webhookUrlTemplate: 'https://myapp.com/webhook?agent={agent_id}&op={operation_id}&type={task_type}',
// OR custom path
webhookUrlTemplate: 'https://myapp.com/api/v1/adcp/{agent_id}?operation={operation_id}',
// OR namespace to avoid conflicts
webhookUrlTemplate: 'https://myapp.com/adcp-webhooks/{agent_id}/{task_type}/{operation_id}'
});// Handles ALL webhooks (task completions and notifications)
app.post('/webhook/:task_type/:agent_id/:operation_id', async (req, res) => {
const { task_type, agent_id, operation_id } = req.params;
// Inject URL parameters into payload
const payload = {
...req.body,
task_type,
operation_id
};
// Route to agent client - handlers fire automatically
const agent = client.agent(agent_id);
await agent.handleWebhook(payload, req.headers['x-adcp-signature']);
res.json({ received: true });
});const operationId = createOperationId();
const webhookUrl = agent.getWebhookUrl('sync_creatives', operationId);
// Returns: https://myapp.com/webhook/sync_creatives/agent_x/op_123
// (or whatever your template generates)Get observability into everything happening:
const client = new ADCPMultiAgentClient(agents, {
onActivity: (activity) => {
console.log({
type: activity.type, // 'protocol_request', 'webhook_received', etc.
operation_id: activity.operation_id,
agent_id: activity.agent_id,
status: activity.status
});
// Stream to UI, save to database, send to monitoring
eventStream.send(activity);
}
});Activity types:
protocol_request- Request sent to agentprotocol_response- Response received from agentwebhook_received- Webhook received from agenthandler_called- Completion handler fired
Mental Model: Notifications are operations that get set up when you create a media buy. The agent sends periodic updates (like delivery reports) to the webhook URL you configured during media buy creation.
// When creating a media buy, agent registers for delivery notifications
const result = await agent.createMediaBuy({
campaign_id: 'camp_123',
budget: { amount: 10000, currency: 'USD' }
// Agent internally sets up recurring delivery_report notifications
});
// Later, agent sends notifications to your webhook
const client = new ADCPMultiAgentClient(agents, {
handlers: {
onMediaBuyDeliveryNotification: (notification, metadata) => {
console.log(`Report #${metadata.sequence_number}: ${metadata.notification_type}`);
// notification_type indicates progress:
// 'scheduled' → Progress update (like status: 'working')
// 'final' → Operation complete (like status: 'completed')
// 'delayed' → Still waiting (extended timeline)
db.saveDeliveryUpdate(metadata.operation_id, notification);
if (metadata.notification_type === 'final') {
db.markOperationComplete(metadata.operation_id);
}
}
}
});Notifications use the same webhook URL pattern as regular operations:
POST https://myapp.com/webhook/media_buy_delivery/agent_x/delivery_report_agent_x_2025-10
The operation_id is lazily generated from agent + month: delivery_report_{agent_id}_{YYYY-MM}
All intermediate reports for the same agent + month → same operation_id
Full TypeScript support with IntelliSense:
// All responses are fully typed
const result = await agent.getProducts(params);
// result: TaskResult<GetProductsResponse>
if (result.success) {
result.data.products.forEach(p => {
console.log(p.name, p.price); // Full autocomplete!
});
}
// Handlers receive typed responses
handlers: {
onCreateMediaBuyComplete: (response, metadata) => {
// response: CreateMediaBuyResponse
// metadata: WebhookMetadata
const buyId = response.media_buy_id; // Typed!
}
}Execute across multiple agents simultaneously:
const client = new ADCPMultiAgentClient([agentX, agentY, agentZ]);
// Parallel execution across all agents
const results = await client.getProducts({ brief: 'Coffee brands' });
// results: TaskResult<GetProductsResponse>[]
results.forEach((result, i) => {
const agentId = client.agentIds[i];
console.log(`${agentId}: ${result.status}`);
if (result.status === 'completed') {
console.log(` Sync: ${result.data.products?.length} products`);
} else if (result.status === 'submitted') {
console.log(` Async: webhook to ${result.submitted?.webhookUrl}`);
}
});const client = new ADCPMultiAgentClient(agents, {
webhookSecret: process.env.WEBHOOK_SECRET
});
// Signatures verified automatically on handleWebhook()
// Returns 401 if signature invalidconst agents = [{
id: 'agent_x',
agent_uri: 'https://agent-x.com',
protocol: 'a2a',
auth_token_env: process.env.AGENT_X_TOKEN, // ✅ Secure
requiresAuth: true
}];# .env
WEBHOOK_URL_TEMPLATE="https://myapp.com/webhook/{task_type}/{agent_id}/{operation_id}"
WEBHOOK_SECRET="your-webhook-secret"
ADCP_AGENTS='[
{
"id": "agent_x",
"agent_uri": "https://agent-x.com",
"protocol": "a2a",
"auth_token_env": "AGENT_X_TOKEN"
}
]'
AGENT_X_TOKEN="actual-token-here"// Auto-discover from environment
const client = ADCPMultiAgentClient.fromEnv();All AdCP tools with full type safety:
Media Buy Lifecycle:
getProducts()- Discover advertising productslistCreativeFormats()- Get supported creative formatscreateMediaBuy()- Create new media buyupdateMediaBuy()- Update existing media buysyncCreatives()- Upload/sync creative assetslistCreatives()- List creative assetsgetMediaBuyDelivery()- Get delivery performance
Audience & Targeting:
listAuthorizedProperties()- Get authorized propertiesgetSignals()- Get audience signalsactivateSignal()- Activate audience signalsprovidePerformanceFeedback()- Send performance feedback
Build agent registries by discovering properties agents can sell. Works with AdCP v2.2.0's publisher-domain model.
- Agents return publisher domains: Call
listAuthorizedProperties()→ getpublisher_domains[] - Fetch property definitions: Get
https://{domain}/.well-known/adagents.jsonfrom each domain - Index properties: Build fast lookups for "who can sell X?" and "what can agent Y sell?"
import { PropertyCrawler, getPropertyIndex } from '@adcp/client';
// First, crawl agents to discover properties
const crawler = new PropertyCrawler();
await crawler.crawlAgents([
{ agent_url: 'https://agent-x.com', protocol: 'a2a' },
{ agent_url: 'https://agent-y.com/mcp/', protocol: 'mcp' }
]);
const index = getPropertyIndex();
// Query 1: Who can sell this property?
const matches = index.findAgentsForProperty('domain', 'cnn.com');
// Returns: [{ property, agent_url, publisher_domain }]
// Query 2: What can this agent sell?
const auth = index.getAgentAuthorizations('https://agent-x.com');
// Returns: { agent_url, publisher_domains: [...], properties: [...] }
// Query 3: Find by tags
const premiumProperties = index.findAgentsByPropertyTags(['premium', 'ctv']);import { PropertyCrawler, getPropertyIndex } from '@adcp/client';
const crawler = new PropertyCrawler();
// Crawl agents - gets publisher_domains from each, then fetches adagents.json
const result = await crawler.crawlAgents([
{ agent_url: 'https://sales.cnn.com' },
{ agent_url: 'https://sales.espn.com' }
]);
console.log(`✅ ${result.successfulAgents} agents`);
console.log(`📡 ${result.totalPublisherDomains} publisher domains`);
console.log(`📦 ${result.totalProperties} properties indexed`);
// Now query
const index = getPropertyIndex();
const whoCanSell = index.findAgentsForProperty('ios_bundle', 'com.cnn.app');
for (const match of whoCanSell) {
console.log(`${match.agent_url} can sell ${match.property.name}`);
}Supports 18 identifier types: domain, subdomain, ios_bundle, android_package, apple_app_store_id, google_play_id, roku_channel_id, podcast_rss_feed, and more.
Build a registry service that:
- Periodically crawls agents with
PropertyCrawler - Persists discovered properties to a database
- Exposes fast query APIs using the in-memory index patterns
- Provides web UI for browsing properties and agents
Library provides discovery logic - you add persistence layer.
Simple unified event log for all operations:
CREATE TABLE webhook_events (
id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
operation_id TEXT NOT NULL, -- Groups related events
agent_id TEXT NOT NULL,
task_type TEXT NOT NULL, -- 'sync_creatives', 'media_buy_delivery', etc.
status TEXT, -- For tasks: 'submitted', 'working', 'completed'
notification_type TEXT, -- For notifications: 'scheduled', 'final', 'delayed'
sequence_number INTEGER, -- For notifications: report sequence
payload JSONB NOT NULL,
timestamp TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX idx_events_operation ON webhook_events(operation_id);
CREATE INDEX idx_events_agent ON webhook_events(agent_id);
CREATE INDEX idx_events_timestamp ON webhook_events(timestamp DESC);
-- Query all events for an operation
SELECT * FROM webhook_events
WHERE operation_id = 'op_123'
ORDER BY timestamp;
-- Get all delivery reports for agent + month
SELECT * FROM webhook_events
WHERE operation_id = 'delivery_report_agent_x_2025-10'
ORDER BY sequence_number;For development and testing, use the included CLI tool to interact with AdCP agents.
Save agents for quick access:
# Save an agent with an alias
npx @adcp/client --save-auth test https://test-agent.adcontextprotocol.org
# Use the alias
npx @adcp/client test get_products '{"brief":"Coffee brands"}'
# List saved agents
npx @adcp/client --list-agentsAuto-detect protocol and call directly:
# Protocol auto-detection (default)
npx @adcp/client https://test-agent.adcontextprotocol.org get_products '{"brief":"Coffee"}'
# Force specific protocol with --protocol flag
npx @adcp/client https://agent.example.com get_products '{"brief":"Coffee"}' --protocol mcp
npx @adcp/client https://agent.example.com list_authorized_properties --protocol a2a
# List available tools
npx @adcp/client https://agent.example.com
# Use a file for payload
npx @adcp/client https://agent.example.com create_media_buy @payload.json
# JSON output for scripting
npx @adcp/client https://agent.example.com get_products '{"brief":"..."}' --json | jq '.products'Three ways to provide auth tokens (priority order):
# 1. Explicit flag (highest priority)
npx @adcp/client test get_products '{"brief":"..."}' --auth your-token
# 2. Saved in agent config (recommended)
npx @adcp/client --save-auth prod https://prod-agent.com
# Will prompt for auth token securely
# 3. Environment variable (fallback)
export ADCP_AUTH_TOKEN=your-token
npx @adcp/client test get_products '{"brief":"..."}'# Save agent with auth
npx @adcp/client --save-auth prod https://prod-agent.com mcp
# List all saved agents
npx @adcp/client --list-agents
# Remove an agent
npx @adcp/client --remove-agent test
# Show config file location
npx @adcp/client --show-configProtocol Auto-Detection: The CLI automatically detects whether an endpoint uses MCP or A2A by checking URL patterns and discovery endpoints. Override with --protocol mcp or --protocol a2a if needed.
Config File: Agent configurations are saved to ~/.adcp/config.json with secure file permissions (0600).
See docs/CLI.md for complete CLI documentation including webhook support for async operations.
Try the live testing UI at http://localhost:8080 when running the server:
npm startFeatures:
- Configure multiple agents (test agents + your own)
- Execute ONE operation across all agents
- See live activity stream (protocol requests, webhooks, handlers)
- View sync vs async completions side-by-side
- Test different scenarios (clarifications, errors, timeouts)
const result = await agent.getProducts({ brief: 'Coffee brands' });const result = await agent.createMediaBuy(
{ brief: 'Coffee campaign' },
(context) => {
// Agent needs more info
if (context.inputRequest.field === 'budget') {
return 50000; // Provide programmatically
}
return context.deferToHuman(); // Or defer to human
}
);const operationId = createOperationId();
const result = await agent.syncCreatives(
{ creatives: largeCreativeList },
null, // No clarification handler = webhook mode
{
contextId: operationId,
webhookUrl: agent.getWebhookUrl('sync_creatives', operationId)
}
);
// Result will be 'submitted', webhook arrives later
// Handler fires when webhook receivedContributions welcome! See CONTRIBUTING.md for guidelines.
Apache 2.0 License - see LICENSE file for details.
- Documentation: docs.adcontextprotocol.org
- Issues: GitHub Issues
- Protocol Spec: AdCP Specification