A2A Gateway API

Use the A2A Gateway API when one agent needs to delegate work to a registered peer under workspace policy, approval, loop, identity, and audit controls.

Enterprise only

Not included in DVARA Open Source.

Choose an operation

Endpoint	Purpose
GET /a2a/{agentId}/.well-known/agent-card.json	Read the governed Agent Card
POST /a2a/{agentId}/message:send	Send a message and wait for the result
POST /a2a/{agentId}/message:stream	Send a message and stream task updates
POST /a2a/{agentId}/tasks:get	Read one task
POST /a2a/{agentId}/tasks:list	List tasks
POST /a2a/{agentId}/tasks:cancel	Cancel a task
POST /a2a/{agentId}/tasks:resubscribe	Resume task event streaming
POST /a2a/{agentId}/pushConfig:set	Create or replace push configuration
POST /a2a/{agentId}/pushConfig:get	Read push configuration
POST /a2a/{agentId}/pushConfig:list	List push configurations
POST /a2a/{agentId}/pushConfig:delete	Remove push configuration

Every request uses the target's registered agentId. DVARA resolves the workspace from the bearer API key before it looks up the target.

Send a governed message

Replace the host, target agent ID, and workspace API key:

curl --silent https://<dvara-host>/a2a/<agent-id>/message:send \
  --header 'Authorization: Bearer <your-api-key>' \
  --header 'Content-Type: application/json' \
  --data '{
    "jsonrpc": "2.0",
    "id": "hop-1042",
    "method": "message/send",
    "params": {
      "metadata": {"skill": "summarize"},
      "message": {
        "role": "user",
        "parts": [
          {"kind": "text", "text": "Summarize claim CLM-1042 for review."}
        ]
      }
    }
  }'

A completed peer call returns an A2A message or task inside the JSON-RPC envelope:

{
  "jsonrpc": "2.0",
  "id": "hop-1042",
  "result": {
    "task": {
      "id": "task-7f12"
    }
  }
}

If policy denies the hop, DVARA returns 403 and does not call the peer.

Open Agents → A2A Hops to inspect the source, target, decision, status, and latency. The same hop writes intent and result or denial evidence to Governance → Audit, joined by its trace information.

Diagnose a failed call

A missing, expired, or revoked workspace key returns 401. A key without the required A2A scope returns 403. A target outside the caller's workspace is not exposed. Peer discovery, signature, credential, policy, approval, and loop failures use distinct error codes so you can separate configuration failures from governed denials.

For delegation chains, approval behavior, streaming, push callbacks, and Agent Card trust, continue with Govern agent-to-agent calls with the A2A Gateway.