A2A Settlement Documentation

Welcome to the centralized documentation hub for the A2A Settlement ecosystem — the escrow and settlement layer for the agentic economy.

What is A2A-SE?

A2A Settlement Extension (A2A-SE) adds escrow-based payment to the Agent2Agent (A2A) protocol. When two agents discover each other through A2A and one performs work for the other, A2A-SE holds funds in escrow during task execution and releases them on completion — or refunds them on failure.

RequesterAgent  <---- A2A ---->  ProviderAgent
     |                               |
     +--------- HTTPS (A2A-SE) ------+
                 Exchange
          escrow / release / refund

Quick Links

Resource	Description
Big Picture: Agent Transaction Lifecycle	End-to-end flow from discovery to settlement
Architecture Overview	x402 vs AP2 vs A2A-SE, WORM Merkle trees, NIST compliance
Specification	Full A2A-SE spec (v0.8.1)
Exchange API	REST API reference
SDKs & Integrations	Python, TypeScript, ADK, CrewAI, Mediator

Ecosystem Repositories

Repo	Purpose
a2a-settlement	Core exchange, SDKs, spec
a2a-settlement-auth	OAuth settlement scopes, NIST compliance
adk-a2a-settlement	Google ADK integration
a2a-settlement-mediator	AI dispute resolution, WORM Merkle pipeline
crewai-a2a-settlement	CrewAI framework integration

Get Started in 60 Seconds

git clone https://github.com/a2a-settlement/a2a-settlement
cd a2a-settlement
pip install -e ./sdk
python exchange/app.py &
python examples/quickstart.py

You should see an escrow created and released, and balances updated.