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Send JSON-RPC Request
BETA

Request

Single A2A JSON-RPC 2.0 transport endpoint. The body is a JSON-RPC envelope whose method field selects the operation. Choose a request example (SendMessage, GetTask, CancelTask) to see the payload for each method. On success the response result holds a Task or a Message. All failures — including request-validation errors such as an invalid enum value — are returned as a JSON-RPC error object with HTTP status 200, per the A2A JSON-RPC binding; the endpoint does not use HTTP 4xx status codes to signal application or validation errors.

Security
apiKey
Headers
A2A-Versionstring

A2A protocol version the client targets.

Example:1.0
Bodyapplication/jsonrequired
jsonrpcstringrequired

JSON-RPC protocol version. Always "2.0".

Example:"2.0"
Value:"2.0"
idstring or integerrequired
Example:1
One of:

Client-chosen request identifier, echoed back in the response.

string
methodstringrequired

The A2A method to invoke. Supported values: SendMessage, GetTask, CancelTask. Confirm the exact literals against the Agent Card before use, as additional methods may be added over time.

Example:"SendMessage"
paramsobjectrequired

Method-specific parameters. The shape depends on method — see the request examples on the POST operation for each supported method.

Example:
{
  "message": {
    "messageId": "9229e770-767c-417b-a0b0-f0741243c581",
    "role": "ROLE_USER",
    "parts": [ … ]
  },
  "metadata": {}
}
Payload
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SendMessage",
  "params": {
    "message": { … },
    "metadata": {}
  }
}

Responses

JSON-RPC 2.0 response. On success result is a Task or a Message; on any failure — including validation errors — error is populated (see JSONRPCError). This endpoint always responds with HTTP 200; it does not return HTTP 4xx codes for application or validation errors.

Bodyapplication/json
One of:

JSON-RPC 2.0 success response envelope.

jsonrpcstringrequired

JSON-RPC protocol version. Always "2.0".

Example:"2.0"
Value:"2.0"
idstring or integerrequired
Example:1
One of:

The request identifier echoed back from the request.

string
resultTask (object) or Message (object)required
One of:

A unit of work processed by the agent, tracked through its lifecycle.

Response
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "id": "task-abc123",
    "contextId": "ctx-xyz789",
    "status": { … },
    "artifacts": [ … ]
  }
}