// free tool
Make your agent discoverable.
Build a spec-compliant A2A agent card, or paste an existing one to validate it. Both run in your browser — nothing is uploaded.
{
"protocolVersion": "0.3.0",
"name": "Invoice Assistant",
"description": "Answers questions about invoices and billing history, and drafts payment reminders.",
"url": "https://example.com/a2a",
"version": "1.0.0",
"capabilities": {
"streaming": false,
"pushNotifications": false,
"stateTransitionHistory": false
},
"defaultInputModes": [
"text/plain"
],
"defaultOutputModes": [
"text/plain"
],
"skills": [
{
"id": "search_invoices",
"name": "Search invoices",
"description": "Find invoices by customer, status or date range. Use when the user asks about billing history.",
"tags": [
"billing",
"search"
]
}
],
"securitySchemes": {
"bearer": {
"type": "http",
"scheme": "bearer"
}
},
"security": [
{
"bearer": []
}
]
}No issues — this card is well-formed and discoverable.
Building multi-agent systems? We do A2A integration and agent interop.
Talk to us about itQuestions
What is an agent card?
The /.well-known/agent-card.json file that lets other agents discover yours — its name, what skills it offers, the endpoint to call, and how to authenticate. A2A is to agent-to-agent delegation roughly what OpenAPI is to REST.
Why do skill descriptions matter so much?
Because a delegating agent reads them to decide whether your agent fits the task. A skill called 'search' described as 'searches' won't get chosen over a competitor that says what it searches and when to use it. It's the same dynamic as tool descriptions in a single agent's toolset.
Where does the file go?
At /.well-known/agent-card.json on the domain that hosts your agent, served as application/json with public read access and no auth on that path — discovery has to work before authentication does.
Is A2A stable?
It's young and still moving. Pin the protocolVersion in your card and treat spec updates as recurring maintenance rather than a one-time build.
Does anything get sent to a server?
No. Both building and validating run entirely in your browser — there's no API call and nothing is stored.
// ready_when_you_are
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