> ## Documentation Index
> Fetch the complete documentation index at: https://docs.myrmagent.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Interactive UI (render_ui)

> Declarative in-chat forms, tables, and charts via the A2UI v3.1 stack.

# Interactive UI (`render_ui`)

Myrm ships a **declarative UI artifact** pipeline: the agent calls `render_ui`, the server emits a `UI_UPDATE` SSE event, and the WebUI renders interactive components inline in chat.

## Enable the tool

1. Open **Agent settings** in chat.
2. Turn on **Interactive UI** (`render_ui`).
3. On first run with a workspace, the server seeds `.agent/docs/A2UI_REFERENCE.md` (full props manual).

Turn1 cost is **\~223 tokens** for the slim tool docstring — full component props are **not** inlined in the prompt.

## A2UI v3.1 behavior

| Topic               | Behavior                                                                                                                                                                          |
| ------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Component whitelist | **23** `UIComponentType` values (enum SSOT, front + back)                                                                                                                         |
| Progressive spec    | Simple UIs (text + field + button) need no extra read; for **table / chart / tabs** or **3+ components**, the agent should `file_read_tool` `.agent/docs/A2UI_REFERENCE.md` first |
| Validation          | **Fail-closed** — unknown `type`, empty `components`, invalid graph (`root_ids`/`children`), or malformed `actions` return structured tool errors (no silent skip)                |
| User actions        | Button / form submissions flow back as `UIActionEvent` and continue the agent loop                                                                                                |

## Delivery pipeline (SSE)

Tool execution may run in a LangGraph child asyncio task where `ArtifactContext` ContextVars are not visible. Myrm stashes UI artifacts by assistant `message_id` (run-level bind + post\_run pop) so **`UI_UPDATE` SSE** still reaches the WebUI before `MESSAGE_END`. Covered by integration wiring tests and a **real LLM agent-stream E2E** (not mocked on the critical path).

## JSON shape (adjacency list)

```json theme={null}
{
  "title": "Feedback form",
  "components": [
    {"id": "t1", "type": "text", "props": {"text": "Rate this run"}},
    {"id": "f1", "type": "text_field", "props": {"label": "Comment"}, "bindings": {"value": "$.form.comment"}},
    {"id": "b1", "type": "button", "props": {"label": "Submit"}, "events": {"onClick": "submit"}}
  ],
  "root_ids": ["t1", "f1", "b1"],
  "data": {"form": {"comment": ""}},
  "actions": [{"id": "submit", "type": "submit", "label": "Submit"}]
}
```

## vs competitors

| Product                        | In-chat generative UI                                                                    |
| ------------------------------ | ---------------------------------------------------------------------------------------- |
| **Myrm**                       | 23 typed components, SSE artifact, progressive spec, fail-closed validation              |
| OpenClaw / Codex / Claude Code | No first-class in-chat form renderer                                                     |
| CopilotKit AG-UI               | Web protocol catalog (\~19 basic widgets); no Myrm-style workspace spec seed + enum gate |
| Hermes                         | Text suggestions; no structured chat UI artifact                                         |

For simple clarifying questions, prefer `ask_question_tool` instead of building a full UI.

See also: [Agent configuration — tool loading](/docs/core-concepts/agent-configuration).