Everything you need. Nothing you don't.

FormaTeX ships a complete LaTeX development environment that runs entirely in the browser. CodeMirror 6 with LaTeX syntax highlighting, a resizable split-pane PDF preview, a project file explorer, outline panel, symbols list, minimap, and a full compilation log with parsed error list. Upload images, .bib files, and custom class files. Autosave triggers every 1500ms — closing the tab loses nothing.

WebSocket-based real-time collaboration shipped in February 2026. Invite collaborators by email, assign Editor or Viewer roles, and see live presence indicators with colored avatars derived deterministically from each user's UUID. Viewers are restricted server-side — they cannot broadcast edit events regardless of client state. Opening the same project in two tabs evicts the older connection automatically.

Define a LaTeX document once as a template, mark dynamic values with {{variable}} placeholders, and expose a compile endpoint that accepts plain JSON. Your callers never touch LaTeX — they POST a JSON object with variable values and receive a PDF. Templates support uploaded assets (logos, .bib, .cls files), forking for new variants, and are callable with any API key.

Link any FormaTeX project to a GitHub repository and keep them in sync. Push your LaTeX source, .bib files, and assets to a branch with one click — or trigger a push automatically after every successful compilation. Pull changes from GitHub to restore a previous version or onboard a new collaborator's fork. Works with public and private repositories. Available on Max and Enterprise plans.

The entire FormaTeX compilation surface is a single POST endpoint. No SDK required, no authentication ceremony. Send JSON containing your LaTeX source and engine preference, receive a binary PDF in the response body. Every response includes compilation timing, engine used, and your remaining quota in the headers. Works identically from curl, JavaScript, Python, Go, or any HTTP client.

curl -X POST https://api.formatex.io/api/v1/compile \
  -H "X-API-Key: fex_a8k2mP9..." \
  -H "Content-Type: application/json" \
  -d '{
    "latex": "\\documentclass{article}\\begin{document}Hello\\end{document}",
    "engine": "pdflatex"
  }' \
  --output document.pdf

# Response headers:
# HTTP/1.1 200 OK
# Content-Type: application/pdf
# X-Engine: pdflatex
# X-Compile-Duration-Ms: 94
# X-Compilations-Used: 42
# X-Compilations-Limit: 500

Four compilation modes for every use case. Sync returns the PDF immediately in the response — zero setup. Async enqueues the job and returns a job ID in under 10ms — no connection held open, ideal for batch pipelines. Stream delivers log output line-by-line via SSE as the engine runs — perfect for live progress UIs. Smart compile reads your document preamble, selects the right engine automatically, and retries on transient failure.

FormaTeX ships a first-class MCP server. Add it to Claude Code, Cursor, Windsurf, or any MCP-compatible client and your AI gains direct access to a full LaTeX compilation stack. Compile documents, fill templates with variables, validate syntax, or list available engines — all from within an AI conversation. No terminal switching, no file copying, no context breaks.

// claude_desktop_config.json  (or .claude/claude_code_config.json)
{
  "mcpServers": {
    "formatex": {
      "command": "formatex-mcp",
      "env": {
        "FORMATEX_API_KEY": "fex_a8k2mP9..."
      }
    }
  }
}

// Claude can now:
// "Compile this document with XeLaTeX and show me the PDF"
// "Fill the invoice template for Acme Corp, $12,500 due March 15"
// "Check my LaTeX for syntax errors before I compile"
// "Which engines are available on my plan?"