GroundmailDocs

AI app builders

Use Groundmail in Lovable, Replit, Bolt, Base44, v0, and similar AI builders.

Two kinds of install surface:

  1. Agent tools (MCP) — the builder’s AI can call Groundmail while you develop (Replit one-click MCP; Cursor/Claude via MCP).
  2. App runtime (Secrets + code) — your deployed app sends mail via GROUNDMAIL_API_KEY and POST /emails (or SMTP).

Most guides below cover (2). Replit also has a one-click path for (1).

Pick your builder

Builder Best for Install surface
Lovable React + Supabase apps, chat-driven features Secrets + agent prompt (HTTP or SMTP)
Replit Full-stack Replit Agent projects MCP badge + Secrets + agent prompt
Bolt.new Vite / React prototypes from chat .env + agent prompt
Base44 Base44 apps with optional custom email When to use TX vs built-in mail
v0 Next.js from Vercel v0 Route Handler + Vercel env

Before you paste a prompt

  1. Create a Groundmail account and an API key (gm_…).
  2. Store it as GROUNDMAIL_API_KEY in the builder’s secrets / env UI (server-side only).
  3. For a first send before your domain verifies, use the sandbox rules in Quickstart and Agent skill notes.

Standard env var

GROUNDMAIL_API_KEY=gm_your_key_here

Some builders also accept STX_API_KEY — if their UI suggests that name, map it to the same gm_… value. Prefer GROUNDMAIL_API_KEY in generated code for consistency with our SDK and docs.

Reference