# API skill

Use the $glyphfield-api skill to read Glyphfield's live catalogs and generate SVGs, element briefs and Design Lab documents over HTTP without a browser.

`$glyphfield-api` covers discovery and generation over HTTP, which do not depend on a browser. Use it for template SVGs, background SVGs, element briefs, batch work and apply-ready documents for Design Lab, the Studio's layered composition tool.

## Invocation [#invocation]

```text
Use $glyphfield-api to discover the current slide contract and generate a set
of source-controlled agenda slides for the General Translation identity.
```

## Discovery [#discovery]

1. Read `/api/agent` for the current interfaces, policies, resources and generation kinds.
2. Read `/api/labs` instead of hard-coding the Studio tool list.
3. Read the `/api/materials`, `/api/identities`, `/api/elements` or `/api/catalog` resource the task needs.
4. Read `GET /api/generate` right before building a `POST` body.
5. Use `/openapi.json`, `/llms.txt` or `/llms-full.txt` when the job needs the complete contract.

```bash
curl -fsS http://localhost:3012/api/agent
curl -fsS http://localhost:3012/api/generate
```

## Generation kinds [#generation-kinds]

| Kind              | Result                                                                               |
| ----------------- | ------------------------------------------------------------------------------------ |
| `template`        | An SVG slide, blog cover, OpenGraph image, terminal card or partnership lockup       |
| `background`      | A gradient, grain-gradient, dither, pattern or tactile surface SVG                   |
| `element-brief`   | One catalog element resolved against an identity, as JSON                            |
| `design-sequence` | An apply-ready layered composition with its shader timeline and Browser API commands |

Use `output: "raw"` for a bare SVG from `template` or `background`. Other responses use the JSON envelope. A `design-sequence` document needs the browser for Canvas and WebGL rendering and for raster or motion output.

## Contract rules [#contract-rules]

* Send `Content-Type: application/json` and only the fields that current discovery lists.
* Do not invent identity, material, element, surface or tool IDs.
* Do not send remote asset URLs. Use base64 data URLs, or an authorized browser `File` in the Studio.
* Read the JSON error of a `400`, `413` or `415` response and fix the named field. Do not resend unchanged invalid input. A `429` comes from the deployment's edge rate limit.
* HTTP generation does not change the open Studio project.

For a rendered Design Lab result, continue with [`$glyphfield-studio`](/docs/skills/studio). To check the files, use [`$glyphfield-export`](/docs/skills/export).