Ad Seller Agent¶
The Ad Seller Agent is an IAB OpenDirect 2.1 compliant programmatic advertising seller system. It enables automated ad selling through a RESTful API, supporting the full lifecycle from product discovery through deal execution and post-deal modifications.
Part of the IAB Tech Lab Agent Ecosystem --- see also the Buyer Agent.
Access Methods¶
The seller agent supports three protocols for different use cases:
| Protocol | Endpoint | Best For |
|---|---|---|
| MCP | /mcp/sse |
Automated agent workflows --- structured tool calls, deterministic |
| A2A | /a2a/seller/jsonrpc |
Conversational agent interactions --- natural language, multi-turn |
| REST API | Various endpoints | Human operators, dashboards, non-agent clients |
For agent-to-agent communication, MCP is the primary protocol. A2A adds conversational capabilities for discovery and negotiation.
Key Capabilities¶
- 58 endpoints across 19 categories covering the complete ad selling workflow
- Tiered pricing engine with buyer-context-aware discounts
- Multi-round automated negotiation with configurable strategies
- Formal order state machine with 12 states and 20 transitions
- Post-deal change request management with severity-based routing
- Event bus for full observability of system activity
- Agent-to-agent (A2A) discovery and trust management
- Human-in-the-loop approval gates for high-value decisions
Documentation Sections¶
Getting Started¶
- Quickstart --- install, run, and make your first API call
API Reference¶
- API Overview --- all 58 endpoints grouped by tag
- MCP Protocol --- primary agentic interface (structured tool calls)
- A2A Protocol --- conversational agent-to-agent interface
- Agent Discovery ---
/.well-known/agent.jsonand trust registry - Authentication --- API keys, access tiers, and agent trust
- Quotes --- non-binding price quotes
- Orders --- order creation and state machine transitions
- Change Requests --- post-deal modifications
Architecture¶
- System Overview --- components and how they connect
- Data Flow --- sequence diagrams for key workflows
- Storage --- backend interface and key conventions
State Machines¶
- Order Lifecycle --- 12 states, 20 transitions
- Change Request Flow --- validation and approval pipeline
Event Bus¶
- Event Bus Overview --- all event types and usage
Integration¶
- Buyer Agent Integration --- discovery, auth, and transaction flows
- Negotiation Protocol --- multi-round negotiation mechanics