Health endpoint

Pro

Check if emails can be sent, e.g. from an uptime monitor.

Setup

Generate a token with at least 16 characters and no spaces, e.g. openssl rand -hex 32.
Store it in an environment variable, e.g. LETTERMINT_HEALTH_TOKEN.
Set Health Token to $LETTERMINT_HEALTH_TOKEN.

Usage

curl -H "Authorization: Bearer $LETTERMINT_HEALTH_TOKEN" https://example.com/actions/lettermint/health

The overall status is the worst check result: ok, warning or error.

Status	Response
`ok` or `warning`	`200`
`error`	`503`
Missing/wrong token	`401`
Endpoint turned off	`404`

The endpoint is off without a Health Token or in the Standard edition. Results are cached for 60 seconds to stay within Lettermint’s rate limits. The endpoint also works while the system is offline.

Example response

{
  "status": "warning",
  "date": "2026-11-05T10:00:00+00:00",
  "checks": [
    { "id": "token", "status": "ok", "text": "Lettermint accepts the project API token." },
    { "id": "teamToken", "status": "ok", "text": "Lettermint accepts the team API token." },
    { "id": "usage", "status": "warning", "text": "The monthly volume of the plan is nearly used up, with 46000 of 50000 emails." },
    { "id": "delivery", "status": "ok", "text": "The project is live." },
    { "id": "sender", "status": "ok", "text": "The domain “example.com” of the system email address belongs to the project." },
    { "id": "route", "status": "ok", "text": "Emails use the default route “outgoing” of the project." }
  ],
  "usage": { "used": 46000, "included": 50000, "share": 0.92 }
}

date shows when the checks ran. Match on the check id, not the text, because the text is translated. See all checks.

Troubleshooting

If your monitor can’t send headers, use ?key=… instead. Prefer the header when possible, because query strings end up in server logs.
Some Apache setups drop the Authorization header before it reaches PHP. If you get 401 with the right token, pass the header through or use ?key=….