agui-author

# Authoring generative UI over AG-UI CAO exposes an **AG-UI** stream (`GET /agui/v1/stream`) that any dashboard — CopilotKit, the AG-UI Dojo, or a plain `EventSource` — renders without CAO-specific code. As an agent you can push a **declarative UI intent** onto that stream with the `emit_ui` MCP tool. The operator sees a rendered card, not raw text — and because every provider's intents render uniformly, they can't tell (and don't need to) which CLI agent produced which card. The surface must be enabled on the server (`CAO_AGUI_ENABLED=true` or `CAO_MCP_APPS_ENABLED=true` — the two surfaces share one event source). When it is disabled, `emit_ui` returns `{"ok": false, "reason": "AG-UI surface disabled…"}` — treat that as a no-op, not an error. ## Safety model (why this is always safe to call) You may emit **only** a closed allow-list of named components with JSON props. There is **no HTML, no script, no `eval`, no iframe**. The intent is validated **server-side** against the allow-list before it reaches the stream: - An **off-list** component (e.g. `iframe`, `script`) is **refused** — the tool raises a `ValueError`; nothing is rendered. - `props` must be **JSON-serializable** and are **bounded to 8 KB** — an oversized or non-serializable payload is **rejected** at the `emit_ui` boundary (HTTP 400, the tool raises a `ValueError`), so a bad payload never reaches the bus. - If the AG-UI surface is disabled on the server, the tool **degrades gracefully** (no error) —...