API Reference

Complete reference for the FormatEx REST API. Compile LaTeX documents to PDF with a single HTTP call.

Quick Example

curl -X POST https://api.formatex.dev/api/v1/compile \
  -H "X-API-Key: your-api-key" \
  -H "Content-Type: application/json" \
  -d '{"latex": "\\documentclass{article}\\begin{document}Hello!\\end{document}"}' \
  --output document.pdf

Authentication

Two auth methods: JWT tokens for account management, API keys for compilation.

Users

Manage your profile and view usage statistics. All endpoints require JWT.

API Keys

Create and manage API keys for compilation. All endpoints require JWT.

Compilation

Compile LaTeX to PDF. All compilation endpoints require an API Key.

{
  "latex": "\\documentclass{article}\\begin{document}\\includegraphics{logo}\\end{document}",
  "engine": "pdflatex",
  "files": [
    { "path": "logo.png", "data": "<base64-encoded-content>" },
    { "path": "refs.bib", "data": "<base64-encoded-content>" }
  ]
}

Webhooks

Register HTTP callbacks to receive real-time notifications on compilation events. Requires JWT.

Event Payload

{
  "event": "compile.success",
  "jobId": "uuid",
  "engine": "pdflatex",
  "durationMs": 1240,
  "timestamp": "2026-02-20T14:30:00Z"
}

If a secret is set, the payload is signed with HMAC-SHA256 delivered in the X-Signature header.

Billing

Subscription management via Polar.sh. Requires JWT authentication.

Plans

View available plans and their limits. Public endpoint.

Plan Comparison

MCP Server

Compile LaTeX directly from AI agents — Claude Desktop, Cursor, Claude Code, n8n, and more — with zero local TeX Live installation. Uses your FormatEx API key for authentication.

Available Tools

Setup

# macOS / Linux
go build -o formatex-mcp ./cmd/mcp
sudo mv formatex-mcp /usr/local/bin/

# Windows
go build -o formatex-mcp.exe ./cmd/mcp

{
  "mcpServers": {
    "formatex": {
      "command": "C:\\path\\to\\formatex-mcp.exe",
      "env": {
        "FORMATEX_API_KEY": "fex_your_api_key_here"
      }
    }
  }
}

{
  "mcpServers": {
    "formatex": {
      "command": "/usr/local/bin/formatex-mcp",
      "env": {
        "FORMATEX_API_KEY": "fex_your_api_key_here"
      }
    }
  }
}

Troubleshooting

Errors

All errors return a consistent JSON format with an error message and optional context.

{
  "error": "human-readable error message",
  "plan": "free",
  "limit": 100,
  "used": 100
}