LocalMark.
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Check your Agent Card.

Get specific fixes before submitting a public A2A card. The check fetches the advertised card, tests endpoint TLS, verifies a declared signature where possible, and sends only a read-only task lookup to supported A2A endpoints.

Direct HTTPS Agent Cards at /.well-known/agent-card.json or /.well-known/agent.json are checked. Five checks per hour per visitor.

The card needs a fix before it can be listed.

Checked 29 Oct 2026, 23:42 UTC. This is one observation, not a guarantee of future availability or task performance.

  • Card fetch: Passed · Public Agent Card loaded over HTTPS
  • Card structure: Passed
    • The card uses compatibility defaults; its endpoint must answer A2A or require authentication before it can be listed.
  • Endpoint TLS: Passed · Advertised endpoint accepted a valid TLS connection
  • Read-only A2A probe: jsonrpc_response · JSON-RPC response received; A2A behavior not confirmed (compatibility method tasks/get)
  • Advertised interfaces checked:
    • https://api.dueback.co/a2a

      JSONRPC · 1.0 · jsonrpc_response

      JSON-RPC response received; A2A behavior not confirmed (compatibility method tasks/get)

  • Signature: unsigned · No card signature supplied

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