---
title: "A2A v0.3.0 agent card for the JSON-RPC endpoint"
method: GET
path: "/v1/a2a/agent-card.json"
tags: ["A2A"]
---

# A2A v0.3.0 agent card for the JSON-RPC endpoint

`GET /v1/a2a/agent-card.json`

## Request

- Base URL: `https://api.voidly.ai`
- URL: `https://api.voidly.ai/v1/a2a/agent-card.json`
- Auth: none required

The executable card: protocolVersion 0.3.0, url https://api.voidly.ai/v1/a2a, preferredTransport JSONRPC, the agentKey (X-Agent-Key header) security scheme, every skill with its inputs, and the error codes. The card at https://voidly.ai/.well-known/agent-card.json names the same endpoint; this one is authoritative for skill inputs.

## Response `200`

The agent card.

- A2AAgentCard
  - `protocolVersion` '0.3.0', required
  - `name` string, required
  - `description` string, required
  - `url` string, uri, required
  - `version` string, required
  - `preferredTransport` 'JSONRPC'
  - `capabilities` object, required
  - `securitySchemes` object
  - `defaultInputModes` string[], required
  - `defaultOutputModes` string[], required
  - `skills` object[], required
    - `id` string, required
    - `name` string, required
    - `description` string, required
    - `tags` string[], required
    - `examples` string[]
    - `inputModes` string[]
    - `outputModes` string[]
    - `security` object[]

## Other responses

- `400`: INVALID_A2A_PATH (the URL carries a query string) or INVALID_A2A_REQUEST (a request body was sent).
- `503`: A2A_READ_ONLY_DISABLED: the endpoint is switched off.

## Changes

- **2026-10-25** `a79d866dc548`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/voidly/apis/voidly-api/changes/v1/a2a/agent-card.json/get.md)

---

[API](https://skmtc.dev/voidly/apis/voidly-api.md) - [All operations](https://skmtc.dev/voidly/apis/voidly-api/llms.txt) - [OpenAPI document](https://skmtc.dev/voidly/apis/voidly-api/revisions/c085ac335933?raw)