canvas

canvas is a skill for Claude Code, Codex from davidtoby/agent-skills. It costs 0 tokens per session (1,421 once invoked), scanned A, a copy of canvas, MIT.

A way to display HTML web content on connected Mac, iPhone, iPad, and Android devices through their OpenClaw canvas views. The content is served by a host and shown in the device app.

In plain words
What is it for?
Showing dashboards, games, visualisations, generated HTML, and interactive demonstrations on connected devices.
Why use it?
It lets a coding agent present a web page or interactive view on another connected device instead of only in the terminal. The host and device connection must be configured.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/davidtoby/agent-skills/canvas
Any agent
npx skills add davidtoby/agent-skills --skill canvas
Clone the repo
git clone --depth 1 https://github.com/davidtoby/agent-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for canvas

README.md
[![agentmods](https://agentmods.dev/badge/skills/davidtoby/agent-skills/canvas.svg)](https://agentmods.dev/skills/davidtoby/agent-skills/canvas)
Your own site
<a href="https://agentmods.dev/skills/davidtoby/agent-skills/canvas"><img src="https://agentmods.dev/badge/skills/davidtoby/agent-skills/canvas.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,421 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
Origin 88% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00000 $0.01421
Opus 5 $0.00000 $0.00711
Sonnet 5 $0.00000 $0.00284
Haiku 4.5 $0.00000 $0.00142

Measured 5d ago against content hash 931e65501872, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

canvas scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

3. Test URL directly: `curl http://<hostname>:18793/__openclaw__/canvas/<file>.html`
Origin

This is a copy

88% identical to canvas — 7 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/.archive/umbrella-curation-2026-04-29/openclaw-imports/canvas/SKILL.md · 199 lines

How it starts

The opening of the file, as written. The whole thing — 199 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Canvas Skill

Display HTML content on connected OpenClaw nodes (Mac app, iOS, Android).

Overview

The canvas tool lets you present web content on any connected node's canvas view. Great for:

  • Displaying games, visualizations, dashboards
  • Showing generated HTML content
  • Interactive demos

How It Works

Architecture

┌─────────────────┐     ┌──────────────────┐     ┌─────────────┐
│  Canvas Host    │────▶│   Node Bridge    │────▶│  Node App   │
│  (HTTP Server)  │     │  (TCP Server)    │     │ (Mac/iOS/   │
│  Port 18793     │     │  Port 18790      │     │  Android)   │
└─────────────────┘     └──────────────────┘     └─────────────┘
  1. Canvas Host Server: Serves static HTML/CSS/JS files from canvasHost.root directory
  2. Node Bridge: Communicates canvas URLs to connected nodes
  3. Node Apps: Render the content in a WebView

Tailscale Integration

The canvas host server binds based on gateway.bind setting:

Bind Mode Server Binds To Canvas URL Uses
loopback 127.0.0.1 localhost (local only)
lan LAN interface LAN IP address
tailnet Tailscale interface Tailscale hostname
auto Best available Tailscale > LAN > loopback

Key insight: The canvasHostHostForBridge is derived from bridgeHost. When bound to Tailscale, nodes receive URLs like:

http://<tailscale-hostname>:18793/__openclaw__/canvas/<file>.html

This is why localhost URLs don't work - the node receives the Tailscale hostname from the bridge!

Actions

Action Description
present Show canvas with optional target URL
hide Hide the canvas
navigate Navigate to a new URL
eval Execute JavaScript in the canvas
snapshot Capture screenshot of canvas

Read the full file on GitHub · 199 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 199 lines · 0 tokens per session scan A 931e65501872

Subscribe to this mod's changes

canvas is a skill published in the GitHub repository davidtoby/agent-skills (10 stars, last pushed 1mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,421 tokens. A static security scan graded it A with 1 finding (makes network calls). It is 88% identical to canvas, differing in 7 lines, and is treated as a copy.

Related

Other skills, from other repositories

officecli-pitch-deck

Use this skill when the user is building a fundraising / investor pitch deck — seed, Series A / B / C, convertible note, SAFE round, strategic raise. Trigger on: 'pitch deck', 'investor deck', 'Series A deck', 'Series B deck', 'Series C deck', 'fundraising deck', 'seed pitch', 'VC deck', 'raising capital', 'term sheet…

iOfficeAI/OfficeCLI · 163 tokens

morph-ppt

Use this skill when the user wants a .pptx with smooth cross-slide animation — PowerPoint Morph transitions, Keynote-style continuous motion, shapes that grow / move / rotate as the slide advances. Trigger on: 'morph', 'morph transition', 'smooth transition', 'continuous animation across slides', 'Keynote-style…

iOfficeAI/OfficeCLI · 169 tokens

officecli-academic-paper

Use this skill to build academic-style .docx output: journal / conference / thesis chapters carrying formal citation style (APA, Chicago, IEEE, MLA), numbered equations, figure & table cross-references, footnotes/endnotes, bibliography, or multi-column journal layout. Trigger on: 'research paper', 'journal paper'…

iOfficeAI/OfficeCLI · 141 tokens

officecli-pptx

Use this skill any time a .pptx file is involved -- as input, output, or both. This includes: creating slide decks, pitch decks, or presentations; reading, parsing, or extracting text from any .pptx file; editing, modifying, or updating existing presentations; combining or splitting slide files; working with…

iOfficeAI/OfficeCLI · 106 tokens

officecli-word-form

Use this skill to create fillable Word forms (.docx) with real Content Controls (SDT) + legacy FormField checkboxes + MERGEFIELD mail-merge placeholders + document protection. Trigger on: 'fillable form', 'form fields', 'content controls', 'SDT', 'word form', 'fill in', 'only editable fields', 'protect document'…

iOfficeAI/OfficeCLI · 224 tokens

officecli-data-dashboard

Use this skill to build a multi-element Excel dashboard — Dashboard sheet on open, multiple formula-driven KPI cards, multiple charts, sparklines, and conditional formatting — from CSV or tabular input. Trigger on: 'dashboard', 'KPI dashboard', 'analytics dashboard', 'executive dashboard', 'metrics dashboard', 'CSV to…

iOfficeAI/OfficeCLI · 157 tokens