Use with a no-code tool

Call the relay from Zapier, Make, Power Automate or any tool that can send an HTTP request.

The recipe

In your tool, add an HTTP action or module, then set:

Setting	Value
Method	POST, or GET for /api/version
Address	https://<host>/api/enveloppe or https://<host>/api/message
Headers	x-functions-key: <key> and Content-Type: application/json, plus x-relay-key if you turned it on
Body	The JSON described in Relay API

Depending on the tool and your plan, the HTTP action may not be offered: check with its vendor.

If the tool offers several request types, choose the one that lets you write the body yourself, often named Custom Request or Raw. Avoid modes that automatically copy the trigger's fields: the body must be exactly the expected JSON.

Common pitfalls

• Types. Numbers and booleans are written without quotes: "maximumOpenTime": 5, not "maximumOpenTime": "5". A list is written in brackets: "authorizedExtensions": [".pdf"]. Otherwise, the relay answers 400 Invalid JSON body.
• Values inserted from the trigger. A quote or a line break in a value breaks the JSON. Use your tool's JSON escaping function, if it has one.
• Reading the response. Parse the response as JSON: in the raw text, & appears as &. The link is in url for an envelope, and in recipients[0].url for a message.
• The status of each recipient. For a message, make the step fail if a recipients[i].status is not 200.

What remains in the tool

The tool's history usually keeps requests and responses: message content, password, links. Limit their retention period, reserve access to the scenarios to the people who need it, and do not put the key in a variable visible to everyone.