extension-sdk-reference SKILL.md skillB
extension-sdk-reference from pizzaface/pizzapi is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add pizzaface/pizzapi/extension-sdk-reference@git:20261008.d2fc60aPins git:20261008.d2fc60a in mdr.lock. Pin the fingerprint instead.
- Audit grade
- B, 16 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- pizzaface/pizzapi
- Path
packages/cli/src/skills/extension-sdk-reference/SKILL.md- Versions recorded
- 6
- Latest version
- git:20261008.d2fc60a, committed Oct 8, 2026
- First version recorded
- Aug 17, 2026
- Size
- 44,399 bytes
- Repository stars
- 15
- License
- Apache-2.0
Comprehensive reference for authoring pi extensions and PizzaPi packages. Covers the pi core extension API (events, UI, tools, commands, models), PizzaPi host detection, service messaging, approvals, runner services (panels, triggers, sigils), and the complete authoring workflows.
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
# Extension SDK Reference
The **extension SDK** is divided into two layers: the **pi core** (`@earendil-works/pi-coding-agent`) and **PizzaPi-specific** capabilities (`@pizzapi/extension-sdk`). This skill covers both, their interaction model, and how to ship runner services.
## Mental Model
```
Extension (Session-side code)
├─ subscribes to pi events (session_start, tool_call, etc.)
├─ registers tools, commands, shortcuts
├─ requests user approval via UI
├─ sends messages to agent
└─ detects PizzaPi host & sends service messages
↓↓↓ (via event bus + relay socket)
Runner Service (Daemon-side code)
├─ listens for service messages from sessions
├─ exposes HTTP panel (iframe)
├─ broadcasts triggers (fire events into agent sessions)
└─ resolves sigils ([[type:id]] tokens)
```
---
## Part 1: Pi Core Extension API
### Entry point: Extension factory
Every extension is a **TypeScript module** that default-exports an async factory function:
```typescript
// extensions/my-extension.ts
import type { ExtensionFactory } from "@earendil-works/pi-coding-agent";
export const myExtension: ExtensionFactory = (pi) => {
// One-time setup here.
…Read the whole file at its exact version.
How to install
mdr add pizzaface/pizzapi/extension-sdk-reference@sha256:b1bd3d0f2d0b2727The line at the top of this page pins the label git:20261008.d2fc60a, 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_4vck74br7322o5x4)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 6 versions of this file, between Aug 17, 2026 and Oct 8, 2026, about one every 11 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261008.d2fc60a latest | 2026-10-08 | d2fc60a | 44,399 B | B | view · diff |
| git:20260925.8191027 | 2026-09-25 | 8191027 | 41,631 B | B | view · diff |
| git:20260924.7a6c2e7 | 2026-09-24 | 7a6c2e7 | 41,261 B | B | view · diff |
| git:20260916.25d89d3 | 2026-09-16 | 25d89d3 | 40,878 B | B | view · diff |
| git:20260821.ea4bb46 | 2026-08-21 | ea4bb46 | 40,671 B | B | view · diff |
| git:20260817.6cf0231 | 2026-08-17 | 6cf0231 | 40,605 B | B | view |
Audit of the latest version
- 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 (44399 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
- pass: No link to a raw IP address
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
pizzaface/pizzapi · 15 stars · license Apache-2.0 · pushed 2026-10-21 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_4vck74br7322o5x4 GET https://markdownregistry.com/api/v1/resolve?ref=pizzaface/pizzapi/extension-sdk-reference GET https://markdownregistry.com/api/v1/blob/b1bd3d0f2d0b27275cd7e18233292afb37727e8026b12c9ac2056da286f2a15d
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.