canvas-webapp SKILL.md skillC
canvas-webapp from blackbelttechnology/pi-agent-dashboard is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add blackbelttechnology/pi-agent-dashboard/canvas-webapp@git:20260815.b32439ePins git:20260815.b32439e in mdr.lock. Pin the fingerprint instead.
- Audit grade
- C, 15 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- blackbelttechnology/pi-agent-dashboard
- Path
packages/extension/.pi/skills/canvas-webapp/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260815.b32439e, committed Aug 15, 2026
- Size
- 5,532 bytes
- Repository stars
- 341
- License
- MIT
Render a React/Vite (or any bundled) web app on the pi-dashboard canvas, which loads loopback URLs in a sandboxed opaque-origin iframe. Use when a canvas(target:{kind:"url"|"server"}) target shows up blank white, an empty surface, or a /live/<id> 500 ECONNREFUSED. Covers why Vite dev servers and non-CORS static servers fail there, and the static-build + CORS-server recipe that works.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# canvas-webapp — show a web app on the dashboard canvas
The dashboard opens a loopback `canvas(kind:"url")` target inside a
`sandbox="allow-scripts"` iframe with **no `allow-same-origin`** (opaque origin),
proxied under `/live/<id>/` (`LiveServerViewer.tsx` → `live-server-proxy`). That
sandbox breaks two common serving strategies; this skill is the fix.
## When to Use
Use when you must display a running web app / React / Vite / MUI mockup on the
pi-dashboard canvas via `canvas(target:{kind:"url"|"server"})` and it shows up
blank white, an empty surface, or a `/live/<id>` 500 ECONNREFUSED.
## Procedure
1. **Do NOT point the canvas at a Vite DEV server.** The dashboard proxies
loopback targets under `/live/<id>/`, but Vite dev emits ABSOLUTE asset paths
(`/main.tsx`, `/@vite/client`, and runtime fetches like `/__schema.json`) that
resolve against the dashboard root, not the proxy prefix → 404 → blank page.
2. **Produce a STATIC production build with a RELATIVE base:** a vite config with
`base:'./'`, a dedicated `index.html` entry, and the runtime data
(schema/props) IMPORTED statically (no fetch of an absolute path). Run
`npx vite build --config <config>`.
…Read the whole file at its exact version.
How to install
mdr add blackbelttechnology/pi-agent-dashboard/canvas-webapp@sha256:43de637a73707322The line at the top of this page pins the label git:20260815.b32439e, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_ubmwjvrgvjo74zxb)
7 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Aug 15, 2026.
Audit of the latest version
- fail: No link to a raw IP address (matched: http://127.0.0.1)
- fail: No script tag (matched: <script)
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (5532 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
Starting a new one? Use a template for SKILL.md on mdpantry, which passes every one of these checks and says what to change in it.
Source
blackbelttechnology/pi-agent-dashboard · 341 stars · license MIT · pushed 2026-11-06 · branch develop
API
GET https://markdownregistry.com/api/v1/artifacts/art_ubmwjvrgvjo74zxb GET https://markdownregistry.com/api/v1/resolve?ref=blackbelttechnology/pi-agent-dashboard/canvas-webapp GET https://markdownregistry.com/api/v1/blob/43de637a73707322b432effc7a452d317164b56d1415290302f3791fbe945669
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.