Module: Keycardai::A2A

Defined in:
lib/keycardai/a2a.rb,
lib/keycardai/a2a/wire.rb,
lib/keycardai/a2a/errors.rb,
lib/keycardai/a2a/version.rb,
lib/keycardai/a2a/delegation_client.rb,
lib/keycardai/a2a/service_discovery.rb

Overview

The A2A delegation client and its result type.

Defined Under Namespace

Classes: DelegationClient, DiscoveryError, InvocationError, Result, ServiceDiscovery, Wire

Constant Summary collapse

AGENT_CARD_PATH =

Well-known path of an agent's card, relative to its base URL.

"/.well-known/agent-card.json"
JSONRPC_PATH =

JSON-RPC invocation path, relative to an agent's base URL.

"/a2a/jsonrpc"
PROTOCOL_VERSION =

A2A protocol version spoken by default: the 1.0 generation, which is what keycardai-a2a (Python) and @keycardai/a2a (TypeScript) serve.

"1.0"
LEGACY_PROTOCOL_VERSION =

The 0.3 generation, for agents not yet on 1.0. Pass it as DelegationClient's protocol_version: to send 0.3-shaped requests.

"0.3"
MESSAGE_SEND_METHOD =

JSON-RPC method that delivers a message to a 1.0 agent.

"SendMessage"
LEGACY_MESSAGE_SEND_METHOD =

JSON-RPC method that delivers a message to a 0.3 agent.

"message/send"
PROTOCOL_VERSION_HEADER =

Header carrying the protocol version on a 1.0 request.

"A2A-Version"
LEGACY_PROTOCOL_VERSION_HEADER =

Header carrying the protocol version on a 0.3 request.

"X-A2A-Protocol-Version"
ROLE_USER =

Message roles as the 1.0 protocol names them (0.3 used "user"/"agent").

"ROLE_USER"
ROLE_AGENT = 
"ROLE_AGENT"
VERSION = 
"0.2.0"

Class Method Summary collapse

Class Method Details

.text_message(text) ⇒ Hash

Build A2A 1.0 SendMessage params carrying one text part, the common case for driving a downstream agent. A client configured for 0.3 translates the role and part shape on the way out.

Parameters:

  • text (String)

Returns:

  • (Hash) 


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# File 'lib/keycardai/a2a/delegation_client.rb', line 108

def self.text_message(text)
  {
    "message" => {
      "role" => ROLE_USER,
      "parts" => [{ "text" => text }],
      "messageId" => SecureRandom.uuid
    }
  }
end