/goose-graphics-create-format

name: goose-graphics-create-format
description: >
  Creates a new graphics format spec (custom canvas dimensions + content rules)
  and publishes it to the Gooseworks library so any agent can render against it.
  Use when the existing community formats (carousel, story, infographic, slides,
  poster, chart, tweet, plus community additions) don't fit the user's canvas —
  e.g., LinkedIn banner 1584×396, story cover 1080×1920, event flyer 8.5×11in.
  Mirrors goose-graphics-create-style but for formats.
tags: [design, content]

Create Goose Graphics Format

Authors a new graphics format and publishes it to the central Gooseworks library via `npx gooseworks formats publish`. The output is a working directory with a `gooseworks-format.json` manifest plus at least one rendered example PNG paired with an existing style.

When to use this skill

Use when the user wants a new named format with its own content rules — a story cover, a podcast cover, a square testimonial — that maps to one of the seven built-in canvas sizes (carousel, infographic, slides, poster, story, chart, tweet). The new format defines new rules and a new slug; it inherits dimensions from one of those canvases.

**Custom canvas dimensions are not supported.** If the user wants a canvas size that isn't in the seven built-ins (e.g. LinkedIn banner 1584×396, US Letter 2550×3300), tell them honestly — that requires a code change to the `goose-graphics` skill pack's `FORMAT_CONFIGS` and is out of scope for this skill. Suggest the closest existing canvas instead.

**Always check first:** run `npx gooseworks formats list` (or `formats search "banner"` etc.) to see whether a community-published format already covers the use case. If one fits, just use it via the regular `goose-graphics` flow.

Prerequisites

• The `goose-graphics` skill must be installed in the same workspace —

this skill uses `goose-graphics/screenshot/screenshot.js` to render examples and pulls style specs via `npx gooseworks styles get <slug>`. Install via:

  npx gooseworks install --claude --with goose-graphics

(Swap `--claude` for `--cursor` or `--codex` as needed.) See the install page on the hub for the canonical command: https://skills.gooseworks.ai/skills/goose-graphics

• The screenshot tool's dependencies must be installed

(`goose-graphics/screenshot/node_modules/` must exist). If not:

  cd <path-to>/goose-graphics/screenshot && npm install && npx playwright install chromium

• The user must be signed in to gooseworks (`npx gooseworks login`) for publish

to authenticate.

Inputs

• A brief describing the canvas: dimensions, intended use (platform / surface),

and content density rules.

• Optional: a reference image showing the desired layout.

Outputs (in a working directory)

<working-dir>/
  gooseworks-format.json    # manifest (see "Manifest format" below)
  example-1.png             # at least one rendered example (REQUIRED)
  example-2.png             # optional; recommend 2–3 examples across styles
  example-3.png

The backend rejects publish with an empty `examples` array — at least one rendered example is mandatory.

Workflow

Step 1 — Pick a canvas (from the fixed allow-list) and confirm intent

A new format is **a new slug + new content rules over one of the seven built-in canvas sizes** — *not* a new canvas. Custom dimensions are not supported: every renderer in the system (CLI screenshot tool, hub, other agents) is locked to this allow-list, and creating a format with custom `width`/`height` would produce something nobody can render.

Pick the canvas the new format should use:

| Canvas slug | Dimensions | Best for | |---------------|------------|--------------------------------------------| | `poster` | 1080×1350 | Vertical hero composition, single panel | | `infographic` | 1080×var. | Tall vertical scroll, multi-section | | `carousel` | 1080×1080 | Square single panel / multi-slide | | `slides` | 1920×1080 | Widescreen / presentation | | `story` | 1080×1920 | Vertical full-screen (IG/TikTok stories) | | `chart` | 1080×1080 | Square data viz | | `tweet` | 1080×1080 | Square testimonial / social card |

Then ask the user:

• Which canvas best fits the use case? (Pick from the table above.)
• What is this format for? (Surface, platform, audience.)
• What is the maximum content density? (Title length, body length, item

counts, whether it's single-panel or multi-panel.)

The new format inherits the canvas's `width`/`height` exactly. Set the manifest's `width`/`height` fields to the canvas's dimensions verbatim (e.g. 1080/1350 for a poster-canvas format). Do not invent new dimensions — the publish step will reject anything that doesn't match one of the seven canvases.

If the user wants a canvas that isn't in the list (e.g. LinkedIn banner 1584×396), tell them honestly: that's a code change to the `goose-graphics` skill pack's `FORMAT_CONFIGS` and is out of scope for this skill. Suggest the closest existing canvas instead.

Step 2 — Pick a name and slug

Suggest 2–3 descriptive names that lead with the platform / surface (e.g., `linkedin-banner`, `story-cover`, `podcast-cover`, `event-flyer-letter`). Slug must be lowercase-kebab-case (`[a-z0-9-]+`).

**Collision check:** run `npx gooseworks formats get <slug>` — if the catalog returns a hit, the slug is taken. Suggest an alternative.

(The user may omit `slug` from the manifest; the backend auto-generates one. On 409 the CLI prompts you to accept the server's suggested slug; pass `--yes` at publish time to auto-accept.)

Step 3 — Draft `contentRulesMd`

This is the load-bearing field — it teaches future agents how to fill the canvas. Cover, in this order:

• **When to use this format vs the alternatives.** One or two sentences.
• **Maximum content density.** Ex