Show widget

기준일: 2026-07-26
난이도: 중급
공식 기준: Show widget

개요

이 페이지는 OpenClaw Show widget 도구(파라미터, 권한, 설정, CLI)를 공식 문서 기준으로 정리합니다.

공식 요약: Show self-contained HTML widgets on supported chat surfaces

도구 가시성은 profile / allow·deny policy / sandbox / channel 권한에 따라 달라집니다. 최신 스키마는 항상 공식 문서를 우선합니다.

공식 문서 기반 상세

아래는 공식 tools/show-widget 문서를 정리한 내용입니다. 코드 블록, 파라미터 이름, 기본값은 원문 그대로입니다.

show_widget is a core tool that shows a self-contained HTML widget on the user's current surface. OpenClaw renders it inline in the Control UI and in iOS, Android, macOS, and Linux Quick Chat transcripts; the Linux dashboard uses the browser Control UI. In a Discord session with Activities enabled, the Discord plugin posts an Open widget button that launches it as an Activity.

How widgets work

When the agent calls show_widget, OpenClaw core wraps widget_code in a minimal HTML document, stores it as a Canvas document, and returns a preview handle. The Control UI renders that handle in a sandboxed iframe, while iOS, Android, macOS, and Linux Quick Chat use isolated web views. Full chat clients restore the widget after history reload; Quick Chat keeps the widget for its active reply.

In Control UI sessions, a Canvas widget can also be pinned to the session dashboard. Set pin: true in the tool call, or use Pin to dashboard on an existing transcript widget. Pinned HTML runs behind the same dedicated-origin, double-iframe sandbox host used by MCP Apps; the browser never resolves a widget data binding inside the untrusted frame.

For browser embedding, the wrapper document injects four small host bridges around the widget code:

• A size reporter posts the rendered content height to the embedding chat, which clamps it and fits the iframe (160 to 1200 pixels).
• A host bridge defines the legacy sendPrompt(text) helper plus the structured openclaw.prompt, openclaw.state, openclaw.data, and openclaw.cron APIs. Inline chat prompts retain their private message channel; dashboard APIs use a view-ticket-bound request channel. See Interactive widgets and Dashboard capabilities.
• A theme bridge listens for the Control UI's current design tokens and applies them as CSS variables, on load and again on every theme change.
• A snapshot bridge renders the current widget document as a PNG when the embedding chat requests an export.

Everything else stays inside the frame: the document runs in an opaque origin with a strict Content Security Policy, so widget scripts cannot reach the Control UI, the Gateway, or the network.

The core implementation is available only when the originating Gateway client declares the inline-widgets capability. The Control UI and supported native apps declare this capability automatically. Linux Quick Chat stays text-only for Gateway connections that require a custom TLS leaf pin because its platform WebView cannot bind that pin. The Discord implementation is available only in Discord sessions with Activities configured. Other channel runs do not receive show_widget.

Capability transport covers embedded, Codex app-server, and CLI-backed model backends. Grant-authenticated MCP callers and direct HTTP tool-invoke callers remain fail closed because they do not declare client capabilities.

Design system

Every Canvas widget includes a classless base stylesheet and a small token set:

Token	Purpose
--surface	Page-level surface color
--card	Card, button, and code background
--elevated	Elevated form-control background
--text	Default body and control text
--text-strong	Headings and prominent values
--muted	Secondary text and subtle borders
--border	Standard separators and card borders
--border-strong	Strong control borders
--accent	Links and focus rings
--accent-fill	Primary action fill
--accent-fg	Text on a primary action
--ok	Success state
--warn	Warning state
--danger	Error or destructive state
--info	Informational state
--radius	Shared control and card corner radius
--font-body	Host body font stack
--font-mono	Host monospace font stack
--accent-subtle, --ok-subtle, --warn-subtle, --danger-subtle, --info-subtle	Derived translucent state backgrounds

Bare headings, paragraphs, links, buttons, inputs, selects, textareas, tables, and code blocks receive base styles. Helper classes provide common patterns:

• .card for a bordered content surface
• .badge, plus .ok, .warn, .danger, or .info, for compact status labels
• .metric for a prominent numeric value
• .muted for secondary text
• .row for a wrapping horizontal layout
• button.primary for the primary action

The Control UI posts an openclaw:widget-theme message with the active theme values when a widget loads and whenever the theme changes. Widgets therefore track every theme family, including Claw, Knot, Dash, and custom themes, without reloading. Outside the Control UI, including native apps and direct opens, widgets use the baked light or dark palette selected by prefers-color-scheme.

Author widgets with three rules:

1. Use the design variables for every color and background. Do not hardcode color values.
2. Keep the page background transparent so the widget belongs to its host surface.
3. Reserve --accent-fill for at most one primary action.

Export: In web chat, open the widget card menu to copy the rendered widget to the clipboard or download it as a PNG. Older widget documents without the snapshot bridge fall back to an HTML file download.

Use the tool

Both implementations use the same required fields:

• title (string) (required): Short title shown with the inline preview and in the hosted document title.

• widget_code (string) (required): Self-contained HTML or SVG. For inline-widget clients, input beginning with <svg after trimming is rendered in SVG mode; maximum length is 262,144 characters. Discord accepts a complete HTML document or body fragment up to 48 KiB.

Discord also accepts optional button_label text for the Activity launch button. The Canvas schema intentionally omits this Discord-only field.

The core Canvas tool accepts these optional dashboard placement fields:

• pin: also place the widget on the session dashboard.
• name: stable widget name; defaults to a slug of title.
• tab: destination tab slug.
• size: one of sm, md, lg, xl, or full.
• after: sibling widget name after which to place the widget.
• capabilities: access requested by a pinned widget. netOrigins contains exact HTTPS origins; tools contains prompt, an allowlisted read binding, or an exact cron.trigger:<jobId> action.

The core result includes a Canvas preview handle, so the Control UI and supported native apps render the widget directly from the tool call and restore it after history reload. Pinned results also retain the board widget name so the Control UI does not offer a duplicate pin after transcript reload. Discord returns the stored widget and posted-message identifiers.

discord_widget remains registered as a deprecated alias for one release. New agent calls should use show_widget.

Interactive widgets

In the Control UI, widget scripts can drive the conversation. The wrapper document defines a global sendPrompt(text) function; calling it submits text to the chat as if the user had typed and sent the message. Wire it to buttons or other controls to build interactive flows such as pickers, quizzes, or drill-down dashboards. Native apps render interactive widget code but do not expose this chat prompt bridge.

<button onclick="sendPrompt('Show the failing tests in detail')">Failing tests</button>

Every prompt is validated on both sides of the frame boundary:

• sendPrompt requires transient user activation inside the widget: it only works in the few seconds after the user clicks or presses a key in the widget, so wire it to buttons and other click targets — calling it automatically on load does nothing. The bridge keeps the sending endpoint private to itself and fails closed in browsers that do not expose user activation, so widget code cannot bypass the check.
• Prompt authority belongs to the original widget document only. The trusted bridge offers its channel endpoint to the chat before widget code can run or navigate the frame, the chat adopts only that first offer, and the channel dies with the document on navigation. Externally allowed embed URLs are never adopted.
• The widget frame must be visible in the chat transcript and hold focus — an additional host-observed signal that the user is actually interacting with this widget.
• The text must be non-empty after trimming and at most 4,000 characters.
• Prompts starting with / are rejected, so widget code cannot trigger chat commands such as /approve or /stop.
• Each widget document may send at most 10 prompts per rolling minute; excess prompts are dropped silently.

Accepted prompts appear in the transcript as regular user messages and start a normal agent turn in the session that owns the widget. There is no feedback channel into the widget: a dropped prompt fails silently, and the widget cannot read the agent's reply.

Dashboard capabilities

Pinned widgets can use one ticket-bound host API after the operator reviews the declaration shown on the pending card:

• openclaw.prompt.send(text) requires transient user activation and posts a visible composer message. Declaring and receiving the prompt tool grant skips the extra per-click confirmation; validation, focus checks, and rate limits still apply.
• openclaw.state.emit(payload) adds a session notice. Payloads are capped at 8 KiB, and identical client emissions within five seconds are coalesced.
• openclaw.data.read(bindingId, params?) resolves only at the Gateway. Grantable bindings are sessions.list, usage.status, usage.cost, cron.list, cron.status, agents.list, and health.
• openclaw.cron.trigger(jobId) runs an existing job now only when the exact cron.trigger:<jobId> capability was granted.

Network access is separate from host tools. Put exact HTTPS origins in capabilities.netOrigins; after approval, only those origins enter the widget's connect-src. Wildcards, credentials, paths, query strings, and undeclared origins remain blocked. A literal port is allowed only when it is part of the declared origin.

Security and storage

Widget documents use restrictive Content Security Policies. Inline style and script are allowed, while external resource loads remain blocked. Inline transcript widgets cannot fetch the network. A pinned dashboard widget can fetch only exact HTTPS origins that the agent declared and the operator granted.

The Control UI iframe always omits allow-same-origin, even when the global embed mode is trusted, so widget scripts cannot read the parent application origin. Native clients use isolated, nonpersistent web views and block navigation away from the hosted widget. The core document host also serves widgets with a Content-Security-Policy: sandbox allow-scripts response header, so direct rendering still runs the widget in an opaque origin instead of an application origin. Only render widget code you are willing to execute in that isolated frame.

The iframe also follows gateway.controlUi.embedSandbox. The default scripts tier supports interactive widgets while preserving origin isolation.

The accepted WebRTC data-channel egress residual is documented in Dashboard Architecture.

Canvas retains at most 32 widgets per session (or per agent when no session is available). Creating another widget removes the oldest document in that scope.

관련 문서

• Control UI hosted embeds
• Discord Activities
• Canvas node controls
• Gateway protocol client capabilities

검증 체크리스트

• 해당 tool이 활성 profile/policy에서 허용되는지 확인
• sandbox / elevated / host 실행 경로 정책을 이해했는지 확인
• 채널·에이전트 권한과 충돌하지 않는지 확인
• 공식 CLI/--help와 문서 옵션이 버전과 맞는지 확인

관련

• Tools 목록 인덱스
• 공식: Tools overview, Tools and custom providers