Watch AI agents talk to each other.

Where you can build an A2A agent.

These platforms let you build an agent that speaks A2A, so other companies' agents can talk to it. Using one doesn't put an agent on your website by itself; you still publish its agent card on your domain, and that's what our agent checks above.

Google launched A2A in April 2025 with more than 50 partners, and the Linux Foundation runs it now. Not sure which to pick? Platforms to run your own agents compares them.

A2A registries.

Public directories where agents list themselves so other agents can find them. Most listings today are independent agents rather than company websites.

Read the agents series.

A five-part guide to AI agents for business. Parts 3 and 5 cover where agents run and how they reach each other over A2A.

Connect your own agent.

Our agent speaks A2A 0.3, an open protocol for AI agents to find each other and talk. Any agent that can make an HTTPS request can ask it questions, check a website with MachineReady, or pass a message to Dan. Here is everything you need.

What our agent can do

Try it in your language

curl -s https://www.buildmarketing.ai/api/a2a \
  -H 'content-type: application/json' \
  -d '{
    "jsonrpc": "2.0", "id": 1, "method": "message/send",
    "params": { "message": {
      "role": "user", "messageId": "m1",
      "parts": [{ "kind": "text", "text": "What does Build Marketing do?" }]
    } }
  }'

import uuid, requests

URL = "https://www.buildmarketing.ai/api/a2a"
context_id = None

def ask(text):
    global context_id
    message = {"role": "user", "messageId": str(uuid.uuid4()),
               "parts": [{"kind": "text", "text": text}]}
    if context_id:
        message["contextId"] = context_id  # continue the conversation
    body = {"jsonrpc": "2.0", "id": 1, "method": "message/send",
            "params": {"message": message}}
    result = requests.post(URL, json=body, timeout=60).json()["result"]
    context_id = result["contextId"]
    return result["parts"][0]["text"]

print(ask("What does Build Marketing do?"))
print(ask("How AI-ready is example.com?"))

const URL = 'https://www.buildmarketing.ai/api/a2a';
let contextId;

async function ask(text) {
  const message = { role: 'user', messageId: crypto.randomUUID(),
    parts: [{ kind: 'text', text }], ...(contextId && { contextId }) };
  const res = await fetch(URL, {
    method: 'POST', headers: { 'content-type': 'application/json' },
    body: JSON.stringify({ jsonrpc: '2.0', id: 1, method: 'message/send', params: { message } }),
  });
  const { result, error } = await res.json();
  if (error) throw new Error(error.message);
  contextId = result.contextId; // keep the conversation going
  return result.parts[0].text;
}

console.log(await ask('What does Build Marketing do?'));

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "kind": "message",
    "role": "agent",
    "messageId": "…",
    "contextId": "…",
    "parts": [{ "kind": "text", "text": "Build Marketing helps B2B companies…" }]
  }
}

Access and limits

• No key needed. The agent is open to any agent or app. If that ever changes, the card's securitySchemes will say which header to send.
• Answers come back in one reply. Use message/send. Streaming and long-running tasks aren't offered, so message/stream and tasks/get return an error.
• Fair use. Up to 30 messages every 10 minutes from one address; after that the agent asks you to wait a few minutes.
• Works from a browser. Cross-origin requests are allowed, so a web app can call the agent directly.
• Conversations are kept. Dan reads them to improve the agent. Don't send anything private you wouldn't put in an email.

Make your own website agent-ready

To let other agents find yours, publish a card like this at /.well-known/agent-card.json on your own domain, then send our agent to your site with the box at the top of this page to see what it finds.

{
  "protocolVersion": "0.3.0",
  "name": "Acme Sales Agent",
  "description": "Answers questions about Acme's products and pricing.",
  "url": "https://www.acme.com/api/a2a",
  "preferredTransport": "JSONRPC",
  "version": "1.0.0",
  "capabilities": { "streaming": false },
  "defaultInputModes": ["text/plain"],
  "defaultOutputModes": ["text/plain"],
  "skills": [{ "id": "pricing", "name": "Pricing questions",
               "description": "Explains plans and prices.", "tags": ["pricing"] }]
}

Is the rest of your website ready for AI? Check it with MachineReady.