A2A agent card — agent readiness

Why an agent cares

A card is how another agent discovers what this site's agent can do and how to reach it. Crawlers already probe for the path, so a card published in the pre-1.0 shape is a live present-but-wrong surface.

Adoption

Early pilots. Named early adopters exist, behind flags or trials. Nothing has been independently measured yet. For this one in particular, standard inside enterprise agent platforms, still rare on the open web.

Direction of travel: ▲ rising, as at 2026-07-28.

GA inside Microsoft, AWS and Google agent platforms with 150+ supporting organisations, but no verifiably identified public open-web card publisher. Crawler logs show agents requesting the path anyway.

Adopter	Depth	Evidence
Microsoft (Copilot Studio, Azure AI Foundry)	`default-on`	linuxfoundation.org
AWS (Bedrock AgentCore Runtime)	`production`	linuxfoundation.org
Google (Gemini Enterprise)	`production`	a2a-protocol.org
SAP, Salesforce, ServiceNow, Cisco, IBM	`announced`	a2a-protocol.org

What we check

Absence is never a finding. Every check below runs only once agentCardPresent is true, so a site that has not adopted this is not assessed on it and appears in no report. 4 of these 5 can fail it. In a Lumar crawl these land on one row per site, in the crawl-level table where itemType is agent_card.

Check	Severity	Raises	On whose authority
`agentCardInvalidJson`	high	conformance, usability	specification (A2A v1.0.0)
`agentCardMissingFields`	high	conformance, usability	specification (A2A v1.0.0)
`agentCardEndpointNotA2A`	high	usability	specification (A2A v1.0 §5.3 (Method Mapping Reference), §11.3.1)
`agentCardInvalidSignature`	high	conformance, usability	specification (A2A v1.0.0)
`agentCardEndpointUnverified`	informational	nothing	Lumar readiness profile

Examples

Both of these are fixtures the test suite runs through the real collector, not snippets written for a document: the first is a shape we score as valid, the second is one we flag.

correctjsontest/e2e/test-pages/trust/correct.agent-card.json

{
  "name": "Recipe Agent",
  "description": "An A2A agent that helps users with recipes and cooking.",
  "version": "1.0.0",
  "capabilities": { "streaming": true },
  "defaultInputModes": ["text/plain"],
  "defaultOutputModes": ["text/plain", "application/json"],
  "skills": [
    {
      "id": "find-recipe",
      "name": "Find a recipe",
      "description": "Finds recipes by ingredient.",
      "tags": ["recipes", "cooking"]
    }
  ],
  "supportedInterfaces": [
    { "url": "https://recipes.example/a2a/v1", "protocolBinding": "JSONRPC", "protocolVersion": "1.0" }
  ]
}

present but wrongjsontest/e2e/test-pages/trust/issues.agent-card.json

{
  "name": "Broken Agent",
  "description": "Served but missing A2A-required fields (no version/capabilities/modes/skills/endpoint) and carrying a structurally malformed signature.",
  "signatures": [
    { "protected": "eyJhbGciOiJFUzI1NiJ9" }
  ]
}

Specifications

Document	Revision	Kind
A2A protocol specification	`v1.0.0`	specification

Last re-read against the published documents: 2026-08-26.