Validate an A2A (Agent2Agent protocol) Agent Card
Validate an A2A (Agent2Agent protocol) Agent Card: required fields, skill shape, transport names, capability flags - spec v0.3 structural core. Returns errors, interop warnings, and a normalized summary (skills, interfaces, capabilities). Deterministic mini-A2A tooling - check a card before your agent trusts it.
Answeringour last check, 2026-09-24
1 of 1checks answered this week
920 msmedian answer time
$0.002listed price per call
$0.002price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://agent402.tools/api/a2a-card-validate
| Category | Everything else |
|---|---|
| Provider host | agent402.tools |
| Networks | algorand:wGHE2Pwdvd7S12BL5FaOP20EGYesN73ktiC1qzkkit8=, eip155:10, eip155:1329, eip155:137, eip155:143, eip155:42161, eip155:42220, eip155:43114, eip155:4663, eip155:8453, solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp, stellar:pubnet |
| Payment schemes | exact, upto |
| Self-reported calls, 30 days | 5 from 2 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-09-24 | valid payment request | 402 | $0.002 | 920 ms |
Example input (from the provider)
{
"body": {
"card": {
"capabilities": {
"pushNotifications": false,
"stateTransitionHistory": false,
"streaming": true
},
"defaultInputModes": [
"application/json",
"text/plain"
],
"defaultOutputModes": [
"application/json"
],
"description": "A sample A2A Agent Card served as a static example for card tooling. This describes a fictional weather agent, not a live A2A endpoint.",
"name": "Sample Weather Agent",
"preferredTransport": "JSONRPC",
"protocolVersion": "0.3.0",
"provider": {
"organization": "Example Org",
"url": "https://example.com"
},
"skills": [
{
"description": "Returns a city's 5-day forecast.",
"examples": [
"What is the weather in Paris this week?"
],
"id": "get-forecast",
"name": "Get weather forecast",
"tags": [
"weather",
"forecast"
]
}
],
"url": "https://example.com/a2a/v1",
"version": "1.0.0"
}
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"properties": {
"card": {
"description": "the Agent Card JSON (object or JSON string)",
"type": "object"
}
},
"required": [
"card"
]
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"errors": {
"type": "array"
},
"summary": {
"properties": {
"name": {
"type": "string"
},
"skillCount": {
"type": "integer"
}
},
"type": "object"
},
"valid": {
"type": "boolean"
},
"warnings": {
"type": "array"
}
},
"required": [
"valid",
"errors",
"warnings",
"summary"
],
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}