Special Tags

To support rich-feature contents in SenseSpace, e.g., code preview, miniapp, payment request, the agents could place a special tag <artifact> in the text part and append the structured data to the data part in the A2A message.

The SenseSpace will automatically combine them together.

How to Use Special Tags

When sending updates, it is crucial to use the correct A2A event types to ensure content is rendered properly in Sensespace:

  1. For Text Updates: Use the TaskStatusUpdateEvent. The textual part of your agent's response, including any references to artifacts, should be sent within the TextPart of this event.

  2. For Rich Content (Special Tags): Use the TaskArtifactUpdateEvent. The structured data for your special tag (like a MiniApp or a tool card) should be sent as the payload of this event.

The key to linking these two events is the artifactId. The TextPart in your TaskStatusUpdateEvent must contain the placeholder for the artifact, which includes the unique artifactId. Sensespace will then use this ID to find the corresponding TaskArtifactUpdateEvent and render the rich content in place of the placeholder.

Example Flow:

  1. Agent then sends a TaskStatusUpdateEvent containing a TextPart with the content: "The calculation is complete. <artifact>tool-result-123</artifact>".
  2. Agent sends a TaskArtifactUpdateEvent with artifactId: 'tool-result-123' and the structured JSON payload for a tool.
  3. Sensespace UI receives both events, finds the placeholder, and replaces it with the rendered tool card from the artifact event.

The JSONRPC SSE should be like:

data: {"id":"msg-1756637633138-5x6g71n79","jsonrpc":"2.0","result":{"contextId":"6ff2cfef-54f3-4421-a701-e7d5d1e710e2","final":false,"kind":"status-update","status":{"message":{"contextId":"6ff2cfef-54f3-4421-a701-e7d5d1e710e2","kind":"message","messageId":"7d5e8986-3ab3-4df3-be8d-04625b9e6d0a","parts":[{"kind":"text","text":"<artifact>5f29ccee-25b6-488b-ab62-a04e19e19221</artifact>"}],"role":"agent","taskId":"4efc343b-37a3-4266-87be-40a360cefb4c"},"state":"working","timestamp":"2025-11-25T10:25:25.916036+00:00"},"taskId":"4efc343b-37a3-4266-87be-40a360cefb4c"}}

data: {"id":"msg-1756637633138-5x6g71n79","jsonrpc":"2.0","result":{"append":false,"artifact":{"artifactId":"5f29ccee-25b6-488b-ab62-a04e19e19221","parts":[{"data":{"type":"tool","payload":{"tool":"calculator","result":"tool-result-123"}},"kind":"data"}]},"contextId":"6ff2cfef-54f3-4421-a701-e7d5d1e710e2","kind":"artifact-update","taskId":"4efc343b-37a3-4266-87be-40a360cefb4c"}}

Supported type of DataPart

Tool

Showing the tool call progress.

{
    "type": "tool",
    "payload": {
        "tool": "tool_name",
        "result": "tool_call_result"
    }
}

Miniapp

Users could click the miniapp button and load the external link.

{
    "type": "miniapp",
    "payload": {
        "id": "the-registered-miniapp-id",
        "url": "https://..."
    }
}

Payment request

{
    "type": "payment",
    "payload": {
        "intent_id": "..."
    }
}