Lettra developer resources.

Give your agent a font you’re allowed to use, the words, and the scene. Say how the text should move, appear, disappear or react to input.

npx skills add joyco-studio/lettra

pnpm add lettra three

Bake the font first. Lettra loads a metrics JSON and an MSDF atlas PNG, not a font file. Check the filenames, glyph coverage and kerning report.

npx lettra bake font.ttf --charset latin-es --size 64 --pxrange 8 --out public/fonts/display

Import from lettra/three and use the three/webgpu renderer. Load the metrics and atlas, create the text, add text.mesh to the scene, and warm it up before showing it. Check the docs for your installed version.

MIT License, © 2026 joyco.studio. Use, modify and distribute it, commercially too, as long as you keep the copyright notice. No warranty. See the license for exact terms.

Fonts have their own licenses. Lettra’s license doesn’t let you redistribute a third-party font.

• Lettra MIT License

  The license file in the repo.

• Lettra documentation

  Reference, examples and font workflow.

• Lettra source and README

  Source, install and current API.

• Lettra agent skill

  Install the Lettra skill in your agent.

• JOYCO experiments

  More work from the studio.

HTML pages answer GET and HEAD. Accept: text/markdown returns Markdown, text/html returns HTML; q-values are honored. Unsupported types get 406, missing Markdown gets 404. Responses vary by Accept. No auth needed.

curl -i -H 'Accept: text/markdown' https://lettra-landing.vercel.app/curl -i -H 'Accept: text/html' https://lettra-landing.vercel.app/ai

• llms.txt

  Summary, usage and doc links.

• Sitemap

  HTML pages and revision dates.

• Agent guide as Markdown

  Stable Markdown URL.

Lettra runs in your app. This site has no hosted API or MCP server.